<PAGE>
    As filed with the Securities and Exchange Commission on January 20, 2000
                                                               Registration No.
-------------------------------------------------------------------------------
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                             ----------------------

                                    FORM S-8
             REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

                             ----------------------

                                   ECOLAB INC.
             (Exact name of registrant as specified in its charter)

          DELAWARE                                            41-0231510
(State or other jurisdiction of                            (I.R.S. Employer
 incorporation or organization)                          Identification No.)
                             ----------------------
                                  Ecolab Center
                            370 North Wabasha Street
                            St. Paul, Minnesota 55102
                                 (651) 293-2233
               (Address, including zip code, and telephone number,
            including area code, of registrant's principal executive
                                    offices)

                             ----------------------

                        ECOLAB CANADA SHARE PURCHASE PLAN
                            (Full title of the plan)

                             ----------------------

                               KENNETH A. IVERSON
                          VICE PRESIDENT AND SECRETARY
                                   ECOLAB INC.
                                  ECOLAB CENTER
                            370 NORTH WABASHA STREET
                            ST. PAUL, MINNESOTA 55102
                                 (651) 293-2125
              (Name and address, including zip code, and telephone
               number, including area code, of agent for service)

                             ----------------------

                  APPROXIMATE DATE OF COMMENCEMENT OF PROPOSED
                              SALE TO THE PUBLIC:
           IMMEDIATELY UPON THE FILING OF THIS REGISTRATION STATEMENT
                             ----------------------

                         CALCULATION OF REGISTRATION FEE

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------------------------

TITLE OF SECURITIES TO BE      AMOUNT TO BE       PROPOSED MAXIMUM              PROPOSED MAXIMUM             AMOUNT OF
REGISTERED                      REGISTERED        OFFERING PRICE PER SHARE(1)   AGGREGATE OFFERING PRICE(1)  REGISTRATION FEE
------------------------------------------------------------------------------------------------------------------------------
<S>                           <C>                <C>                           <C>                          <C>
Common Stock, par value
$1.00 per share (2) . . .      50,000 shares                $38.78125                   $1,939,062.50               $511.91
------------------------------------------------------------------------------------------------------------------------------
</TABLE>

(1)      Estimated solely for the purpose of calculating the amount of the
         registration fee pursuant to Rule 457(h) under the Securities Act of
         1933, as amended (the "Securities Act"), on the basis of the average
         between the high and low reported sale prices of the Registrant's
         Common Stock on January 18, 2000 as reported on the New York Stock
         Exchange.

(2)      Each share of Common Stock includes one-half share of an associated
         preferred stock purchase right (a "Right").

--------------------------------------------------------------------------------
<PAGE>

                                     PART II

                              INFORMATION REQUIRED
                          IN THE REGISTRATION STATEMENT

ITEM 3. INCORPORATION OF DOCUMENTS BY REFERENCE.

The following documents filed by Ecolab Inc. (the "Company" or the
"Registrant") (File No. 1-9328) with the Securities and Exchange Commission
(the "Commission") are incorporated by reference in this Registration
Statement: (1) Annual Report on Form 10-K for the year ended December 31,
1998; (2) Quarterly Reports on Form 10-Q for the periods ended March 31, June
30 and September 30, 1999; (3) Current Report on Form 8-K dated March 25,
1999; (4) all other reports filed by the Company pursuant to Sections 13(a)
or 15(d) of the Securities Exchange Act of 1934, as amended (the "Exchange
Act"), since December 31, 1998; and (5) the descriptions of the Company's
Common Stock, Preferred Stock and Rights contained in its Registration
Statements on Form 8-A, including any amendments or reports filed for the
purpose of updating such descriptions.

         All documents filed by the Company with the Commission pursuant to
Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this
Registration Statement and prior to the filing of a post-effective amendment
which indicates that all shares of Common Stock offered pursuant to this
Registration Statement have been sold or that de-registers all shares of
Common Stock then remaining unsold, shall be deemed to be incorporated by
reference in this Registration Statement and to be a part hereof from the
date of filing of such documents.

         The consolidated financial statements and related financial
statement schedule of the Company, which are included or incorporated by
reference in the Company's Annual Report on Form 10-K for the year ended
December 31, 1998, and incorporated by reference in this Registration
Statement, have been audited by PricewaterhouseCoopers LLP, independent
accountants, for the periods indicated in such firm's reports thereon. The
consolidated financial statements and financial statement schedule audited by
PricewaterhouseCoopers LLP have been incorporated herein by reference in
reliance on such firm's reports given upon their authority as experts in
accounting and auditing. To the extent that PricewaterhouseCoopers LLP
examines and reports on the financial statements and financial statement
schedules of the Company issued at future dates, and consents to the use of
their reports thereon, such financial statements and financial statement
schedules will also be incorporated by reference in this Registration
Statement in reliance upon their reports and said authority.

         With respect to unaudited interim financial information incorporated
by reference in this Registration Statement, PricewaterhouseCoopers LLP has
reported that they have applied limited procedures in accordance with
professional standards for reviews of such information. However, their
separate reports, incorporated by reference herein, state that they did not
audit and they do not express an opinion on that interim financial
information. Accordingly, the degree of reliance on their reports on such
information should be restricted in light of the limited nature of the review
procedures applied. The independent accountants are not subject to the
liability provisions of Section 11 of the Securities Act for their reports on
the unaudited interim financial information because each such report is not a
"report" or a "part" of the Registration Statement prepared or certified by
the independent accountants within the meaning of Sections 7 and 11 of the
Securities Act.

         In addition, the combined financial statements and related financial
statement schedule of the Henkel-Ecolab Joint Venture as of November 30, 1998
and for the year ended November 30, 1998, which

                                       2

<PAGE>

are included in the Company's Annual Report on Form 10-K for the year ended
December 31, 1998, and incorporated by reference in this Registration
Statement, have been audited by PricewaterhouseCoopers Gesellschaft mit
beschrankter Haftung Wirtschaftsprufungsgesellschaft, independent
accountants. The combined financial statements and related financial
statement schedule audited by PricewaterhouseCoopers Gesellschaft mit
beschrankter Haftung Wirtschaftsprufungsgesellschaft have been incorporated
herein by reference in reliance on such firm's reports given upon their
authority as experts in accounting and auditing. To the extent that
PricewaterhouseCoopers Gesellschaft mit beschrankter Haftung
Wirtschaftsprufungsgesellschaft examines and reports on the financial
statements and financial statement schedules of the Henkel-Ecolab Joint
Venture issued at future dates, and consents to the use of their reports
thereon, such financial statements and financial statement schedules will
also be incorporated by reference in this Registration Statement in reliance
upon their reports and said authority.

         In addition, the combined balance sheets of the Henkel-Ecolab Joint
Venture as of November 30, 1997 and 1996, and the related combined statements
of income, equity and cash flows for each of the periods beginning December
1, 1996 and 1995 and ended November 30, 1997 and 1996, respectively, and
related financial statement schedule for the same periods (collectively, the
"1996 and 1997 Henkel-Ecolab Joint Venture Financials"), which are included
in the Company's Annual Report on Form 10-K for the year ended December 31,
1998, and incorporated by reference in this Registration Statement, have been
audited by KPMG Deutsche Treuhand-Gesellschaft Aktiengesellschaft
Wirtschaftsprufungsgesellschaft, independent accountants. The 1996 and 1997
Henkel-Ecolab Joint Venture Financials audited by KPMG Deutsche
Treuhand-Gesellschaft Aktiengesellschaft Wirtschaftsprufungsgesellschaft have
been incorporated herein by reference in reliance on such firm's reports
given upon their authority as experts in accounting and auditing.

ITEM 4. DESCRIPTION OF SECURITIES.

         Not applicable - the Company's Common Stock and Rights to be offered
pursuant to this Registration Statement have been registered under Section 12
of the Exchange Act as described in Item 3 of this Part II.

ITEM 5. INTERESTS OF NAMED EXPERTS AND COUNSEL.

         Not applicable.

ITEM 6. INDEMNIFICATION OF DIRECTORS AND OFFICERS.

         Subsection (a) of Section 145 of the General Corporation Law of
Delaware ("DGCL") empowers a corporation to indemnify any person who was or
is a party or is threatened to be made a party to any threatened, pending or
completed action, suit or proceeding, whether civil, criminal, administrative
or investigative (other than an action by or in the right of the
corporation), by reason of the fact that such person is or was a director,
officer, employee or agent of the corporation or is or was serving at the
request of the corporation as a director, officer, employee or agent of
another corporation or enterprise, against expenses (including attorneys'
fees), judgments, fines and amounts paid in settlement actually and
reasonably incurred by such person in connection with such action, suit or
proceeding if such person acted in good faith and in a manner such person
reasonably believed to be in or not opposed to the best interests of the
corporation, and with respect to any criminal action or proceeding, had no
reasonable cause to believe such person's conduct was unlawful.

         Subsection (b) of Section 145 empowers a corporation to indemnify
any person who was or is a party or threatened to be made a party to any
threatened, pending or completed action or suit by or in the right of the
corporation to procure a judgment in its favor by reason of the fact that
such person acted in any of the

                                       3

<PAGE>

capacities set forth above, against expenses actually and reasonably incurred
by such person in connection with the defense or settlement of such action or
suit if such person acted under similar standards, except that no
indemnification may be made in respect of any claim, issue or matter as to
which such person shall have been adjudged to be liable to the corporation
unless and only to the extent that the Court of Chancery or the court in
which such action or suit was brought shall determine that, despite the
adjudication of liability, such person is fairly and reasonably entitled to
indemnity for such expenses which the court shall deem proper.

         Section 145 further provides that, to the extent a director or
officer of a corporation has been successful in the defense of any action,
suit or proceeding referred to in subsections (a) and (b) or in the defense
of any claim, issue or matter therein, such person shall be indemnified
against expenses (including attorneys' fees) actually and reasonably incurred
in connection therewith; that indemnification provided for by Section 145
shall not be deemed exclusive of any other rights to which the indemnified
party may be entitled; and that the scope of indemnification extends to
directors, officers, employees or agents of a constituent corporation
absorbed in a consolidation or merger and persons serving in that capacity at
the request of the constituent corporation for another. Section 145 also
empowers the corporation to purchase and maintain insurance on behalf of a
director or officer of the corporation against any liability asserted against
or incurred by such person in any such capacity or arising out of such
person's status as such, whether or not the corporation would have the power
to indemnify such person against such liabilities under Section 145,
including liabilities under the Securities Act.

         Article V of the Company's By-Laws provides for indemnification of
the Company's officers and directors to the full extent allowed by the DGCL.

         In addition, Article IV of the Company's Restated Certificate of
Incorporation provides that the Company's directors do not have personal
liability to the Company or its stockholders for monetary damages for any
breach of their fiduciary duty as directors, except (i) for a breach of the
duty of loyalty, (ii) for acts or omissions not in good faith or which
involve intentional misconduct or knowing violation of the law, (iii) for
willful or negligent violations of certain provisions under the DGCL imposing
certain requirements with respect to stock repurchases, redemptions and
dividends, or (iv) for any transaction from which the director derived an
improper personal benefit. Subject to these exceptions, under Article IV,
directors do not have any personal liability to the Company or its
stockholders for any violation of their fiduciary duty.

         The Company has directors and officers liability insurance which
protects each director or officer from certain claims and suits, including
stockholder derivative suits, even where the director may be determined to
not be entitled to indemnification under the DGCL and claims and suits
arising under the Securities Act. The policy may also afford coverage under
circumstances where the facts do not justify a finding that the director or
officer acted in good faith and in a manner that was in or not opposed to the
best interests of the Company.

         The Company has entered into indemnification agreements with each of
its directors (the "Indemnification Agreements"). The Indemnification
Agreements provide for the prompt indemnification "to the fullest extent
permitted by law" and for the prompt advancement of expenses, including
attorneys' fees and other costs, expenses and obligations paid or incurred in
connection with investigating, defending, being a witness or participating in
(including on appeal) any threatened, pending or completed action, suit or
proceeding related to the fact that such director is or was a director,
officer, employee, trustee, agent or fiduciary of the Company or is or was
serving at the request of the Company as a director, officer, employee,
trustee, agent or fiduciary of another corporation, partnership, joint
venture, employee benefit plan trust or other enterprise, or by reason of
anything done or not done by a director in any such capacity. The
Indemnification Agreements further provide that the Company has the burden of
proving that a director is not entitled to indemnification in any particular
case.

                                       4

<PAGE>

         The foregoing represents a summary of the general effect of the
DGCL, the Company's By-Laws and Restated Certificate of Incorporation, the
Company's directors and officers liability insurance coverage and the
Indemnification Agreements for purposes of general description only.

ITEM 7. EXEMPTION FROM REGISTRATION CLAIMED.

         Not applicable - no securities are to be re-offered or resold
pursuant to this Registration Statement.

ITEM 8.  EXHIBITS.

<TABLE>

<S>     <C>
4.1      Restated Certificate of Incorporation of the Company (incorporated by
         reference to Exhibit (3) to the Company's Current Report on Form 8-K
         dated October 22, 1997 (File No. 1-9328)).
4.2      Bylaws of the Company, as amended through February 18, 1999
         (incorporated by reference to Exhibit (3)B to the Company's Annual
         Report on Form 10-K for the year ended December 31, 1998 (File No.
         1-9328)).
4.3      Form of Common Stock Certificate (incorporated by reference to Exhibit
         4(B) to the Company's Annual Report on Form 10-K for the year ended
         December 31, 1995 (File No. 1-9328)).
4.4      Rights Agreement, dated as of February 24, 1996, between the Company
         and First Chicago Trust Company of New York, as Rights Agent
         (incorporated by reference to Exhibit 4 to the Company's Current Report
         on Form 8-K dated February 24, 1996 (File No. 1-9328)).
15.1     Letter of PricewaterhouseCoopers LLP regarding unaudited interim
         financial information (filed herewith electronically).
23.1     Consent of PricewaterhouseCoopers LLP (filed herewith electronically).
23.2     Consent of PricewaterhouseCoopers GmbH (filed herewith electronically).
23.3     Consent of KPMG Deutsche Treuhand-Gesellschaft Aktiengesellschaft
         Wirtschaftsprufungsgesellschaft (filed herewith electronically).
24.1     Powers of Attorney (filed herewith electronically).

</TABLE>

ITEM 9. UNDERTAKINGS.

(a)      The undersigned Registrant hereby undertakes:

         (1)      To file, during any period in which offers or sales are being
                  made, a post-effective amendment to this registration
                  statement:

                  (i)      To include any prospectus required by Section
                           10(a)(3) of the Securities Act;

                  (ii)     To reflect in the prospectus any facts or events
                           arising after the effective date of the registration
                           statement (or the most recent post-effective
                           amendment thereof) which, individually or in the
                           aggregate, represent a fundamental change in the
                           information set forth in the registration statement.
                           Notwithstanding the foregoing, any increase or
                           decrease in volume of securities offered (if the
                           total dollar value of securities offered would not
                           exceed that which was registered) and any deviation
                           from the low or high end of the estimated maximum
                           offering range may be reflected in the form of
                           prospectus filed with the Commission pursuant to Rule
                           424(b) under the Securities Act if, in the aggregate,
                           the changes in volume and price represent no more
                           than a 20% change in the maximum aggregate offering
                           price set forth in the "Calculation of Registration
                           Fee" table in the effective registration statement;

                  (iii)    To include any material information with respect to
                           the plan of distribution not


                                       5

<PAGE>

                           previously disclosed in the registration statement or
                           any material change to such information in the
                           registration statement;

                  PROVIDED, HOWEVER, that paragraphs (a)(1)(i) and (a)(1)(ii) do
                  not apply if the information required to be included in a
                  post-effective amendment by those paragraphs is contained in
                  periodic reports filed with or furnished to the Commission by
                  the Registrant pursuant to Section 13 or Section 15(d) of the
                  Exchange Act that are incorporated by reference in the
                  registration statement.

         (2)      That, for the purpose of determining any liability under the
                  Securities Act, each such post-effective amendment shall be
                  deemed to be a new registration statement relating to the
                  securities offered therein, and the offering of such
                  securities at that time shall be deemed to be the initial bona
                  fide offering thereof.

         (3)      To remove from registration by means of a post-effective
                  amendment any of the securities being registered which remain
                  unsold at the termination of the offering.

(b)      The undersigned Registrant hereby undertakes that, for purposes of
         determining any liability under the Securities Act, each filing of the
         Registrant's annual report pursuant to Section 13(a) or Section 15(d)
         of the Exchange Act (and, where applicable, each filing of an employee
         benefit plan's annual report pursuant to Section 15(d) of the Exchange
         Act) that is incorporated by reference in the registration statement
         shall be deemed to be a new registration statement relating to the
         securities offered therein, and the offering of such securities at that
         time shall be deemed to be the initial bona fide offering thereof.

(c)      Insofar as indemnification for liabilities arising under the Securities
         Act may be permitted to directors, officers and controlling persons of
         the Registrant, the Registrant has been advised that in the opinion of
         the Commission such indemnification is against public policy as
         expressed in the Securities Act and is, therefore, unenforceable. In
         the event that a claim for indemnification against such liabilities
         (other than the payment by the Registrant of expenses incurred or paid
         by a director, officer or controlling person of the Registrant in the
         successful defense of any action, suit or proceeding) is asserted by
         such director, officer or controlling person in connection with the
         securities being registered, the Registrant will, unless in the opinion
         of its counsel the matter has been settled by controlling precedent,
         submit to a court of appropriate jurisdiction the question whether such
         indemnification by it is against public policy as expressed in the
         Securities Act and will be governed by the final adjudication of such
         issue.


                                       6

<PAGE>

                                   SIGNATURES

THE REGISTRANT. Pursuant to the requirements of the Securities Act of 1933,
the Registrant certifies that it has reasonable grounds to believe that it
meets all of the requirements for filing on Form S-8 and has duly caused this
registration statement to be signed on its behalf by the undersigned,
thereunto duly authorized, in the City of St. Paul, State of Minnesota, on
January 20, 2000.

                                 ECOLAB INC.


                                By: /s/ Allan L. Schuman
                                    ----------------------------------------
                                    Allan L. Schuman
                                    Chairman of the Board, President and Chief
                                    Executive Officer


         Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed on January 20, 2000 by the following
persons in the capacities indicated.



/s/ Allan L. Schuman                   Chairman of the Board, President
----------------------------------     and Chief Executive Officer (Principal
Allan L. Schuman                       Executive Officer) and Director



/s/ L. White Matthews, III             Executive Vice President and Chief
----------------------------------     Financial Officer (Principal Financial
L. White Matthews, III                 Officer) and Director

/s/ Steven L. Fritze                   Vice President and Controller (Principal
----------------------------------     Accounting Officer)
Steven L. Fritze


/s/ Kenneth A. Iverson                 Directors
----------------------------------
Kenneth A. Iverson, as attorney-in-
fact for Les S. Biller, Ruth S. Block,
Jerry A. Grundhofer, James J. Howard,
William L. Jews, Joel W. Johnson,
Jerry W. Levin, Robert L. Lumpkins,
Richard L. Schall, Roland Schulz,
Hugo Uyterhoeven and Albrecht Woeste

Director not signing:  Reuben F. Richards


                                       7

<PAGE>

                                INDEX TO EXHIBITS

<TABLE>
<CAPTION>

ITEM                 DESCRIPTION                                               METHOD OF FILING
NO.                  -----------                                               ----------------
-----
<S>    <C>                                                        <C>
4.1     Restated Certificate of Incorporation of                   Incorporated by reference to Exhibit (3) to
        the Company.........................................       the Company's Current Report on Form 8-K
                                                                   dated October 22, 1997 (File No. 1-9328).

4.2     Bylaws of the Company, as amended                          Incorporated by reference to Exhibit (3)B
        through February 18, 1999...........................       to the Company's Annual Report on Form 10-K
                                                                   for the year ended December 31 1998 (File
                                                                   No. 1-9328).

4.3     Form of Common Stock Certificate....................       Incorporated by reference to Exhibit
                                                                   4(B) to the Company's Annual Report on Form
                                                                   10-K for the year ended December 31, 1995
                                                                   (File No. 1-9328).

4.4     Rights Agreement, dated as of February                     Incorporated by reference to Exhibit 4 to
        24, 1996, between the Company and                          the Company's Current Report on Form 8-K
        First Chicago Trust Company of New                         dated February 24, 1996 (File No. 1-9328).
        York, as Rights Agent...............................

15.1    Letter of PricewaterhouseCoopers LLP regarding
        unaudited interim financial information.                   Filed herewith electronically.

23.1    Consent of PricewaterhouseCoopers LLP.                     Filed herewith electronically.

23.2    Consent of PricewaterhouseCoopers GmbH.                    Filed herewith electronically.

23.3    Consent of KPMG Deutsche Treuhand -                        Filed herewith electronically.
        Gesellschaft Aktiengesellschaft
        Wirtschaftsprufungsgesellschaft.....................

24.1    Powers of Attorney..................................       Filed herewith electronically.

</TABLE>

                                        8
[{"type": "S-8", "sequence": "1", "description": "S-8", "secsgml_size_bytes": 28360}]
{"company-data": {"conformed-name": "ECOLAB INC", "cik": "0000031462", "assigned-sic": "2840", "irs-number": "410231510", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-95041", "film-number": "510340"}, "business-address": {"street1": "ECOLAB CTR", "street2": "370 N WABASHA ST", "city": "ST PAUL", "state": "MN", "zip": "55102", "phone": "6122932233"}, "former-company": {"former-conformed-name": "ECONOMICS LABORATORY INC", "date-changed": "19861203"}}
As filed with the Securities and Exchange Commission on January 20, 2000
                                                               Registration No.
-------------------------------------------------------------------------------
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                             ----------------------

                                    FORM S-8
             REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

                             ----------------------

                                   ECOLAB INC.
             (Exact name of registrant as specified in its charter)

          DELAWARE                                            41-0231510
(State or other jurisdiction of                            (I.R.S. Employer
 incorporation or organization)                          Identification No.)
                             ----------------------
                                  Ecolab Center
                            370 North Wabasha Street
                            St. Paul, Minnesota 55102
                                 (651) 293-2233
               (Address, including zip code, and telephone number,
            including area code, of registrant's principal executive
                                    offices)

                             ----------------------

                        ECOLAB CANADA SHARE PURCHASE PLAN
                            (Full title of the plan)

                             ----------------------

                               KENNETH A. IVERSON
                          VICE PRESIDENT AND SECRETARY
                                   ECOLAB INC.
                                  ECOLAB CENTER
                            370 NORTH WABASHA STREET
                            ST. PAUL, MINNESOTA 55102
                                 (651) 293-2125
              (Name and address, including zip code, and telephone
               number, including area code, of agent for service)

                             ----------------------

                  APPROXIMATE DATE OF COMMENCEMENT OF PROPOSED
                              SALE TO THE PUBLIC:
           IMMEDIATELY UPON THE FILING OF THIS REGISTRATION STATEMENT
                             ----------------------

                         CALCULATION OF REGISTRATION FEE
------------------------------------------------------------------------------------------------------------------------------

TITLE OF SECURITIES TO BE      AMOUNT TO BE       PROPOSED MAXIMUM              PROPOSED MAXIMUM             AMOUNT OF
REGISTERED                      REGISTERED        OFFERING PRICE PER SHARE(1)   AGGREGATE OFFERING PRICE(1)  REGISTRATION FEE
------------------------------------------------------------------------------------------------------------------------------
Common Stock, par value
$1.00 per share (2) . . .      50,000 shares                $38.78125                   $1,939,062.50               $511.91
------------------------------------------------------------------------------------------------------------------------------
(1)      Estimated solely for the purpose of calculating the amount of the
         registration fee pursuant to Rule 457(h) under the Securities Act of
         1933, as amended (the "Securities Act"), on the basis of the average
         between the high and low reported sale prices of the Registrant's
         Common Stock on January 18, 2000 as reported on the New York Stock
         Exchange.

(2)      Each share of Common Stock includes one-half share of an associated
         preferred stock purchase right (a "Right").

--------------------------------------------------------------------------------
PART II

                              INFORMATION REQUIRED
                          IN THE REGISTRATION STATEMENT

ITEM 3. INCORPORATION OF DOCUMENTS BY REFERENCE.

The following documents filed by Ecolab Inc. (the "Company" or the
"Registrant") (File No. 1-9328) with the Securities and Exchange Commission
(the "Commission") are incorporated by reference in this Registration
Statement: (1) Annual Report on Form 10-K for the year ended December 31,
1998; (2) Quarterly Reports on Form 10-Q for the periods ended March 31, June
30 and September 30, 1999; (3) Current Report on Form 8-K dated March 25,
1999; (4) all other reports filed by the Company pursuant to Sections 13(a)
or 15(d) of the Securities Exchange Act of 1934, as amended (the "Exchange
Act"), since December 31, 1998; and (5) the descriptions of the Company's
Common Stock, Preferred Stock and Rights contained in its Registration
Statements on Form 8-A, including any amendments or reports filed for the
purpose of updating such descriptions.

         All documents filed by the Company with the Commission pursuant to
Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this
Registration Statement and prior to the filing of a post-effective amendment
which indicates that all shares of Common Stock offered pursuant to this
Registration Statement have been sold or that de-registers all shares of
Common Stock then remaining unsold, shall be deemed to be incorporated by
reference in this Registration Statement and to be a part hereof from the
date of filing of such documents.

         The consolidated financial statements and related financial
statement schedule of the Company, which are included or incorporated by
reference in the Company's Annual Report on Form 10-K for the year ended
December 31, 1998, and incorporated by reference in this Registration
Statement, have been audited by PricewaterhouseCoopers LLP, independent
accountants, for the periods indicated in such firm's reports thereon. The
consolidated financial statements and financial statement schedule audited by
PricewaterhouseCoopers LLP have been incorporated herein by reference in
reliance on such firm's reports given upon their authority as experts in
accounting and auditing. To the extent that PricewaterhouseCoopers LLP
examines and reports on the financial statements and financial statement
schedules of the Company issued at future dates, and consents to the use of
their reports thereon, such financial statements and financial statement
schedules will also be incorporated by reference in this Registration
Statement in reliance upon their reports and said authority.

         With respect to unaudited interim financial information incorporated
by reference in this Registration Statement, PricewaterhouseCoopers LLP has
reported that they have applied limited procedures in accordance with
professional standards for reviews of such information. However, their
separate reports, incorporated by reference herein, state that they did not
audit and they do not express an opinion on that interim financial
information. Accordingly, the degree of reliance on their reports on such
information should be restricted in light of the limited nature of the review
procedures applied. The independent accountants are not subject to the
liability provisions of Section 11 of the Securities Act for their reports on
the unaudited interim financial information because each such report is not a
"report" or a "part" of the Registration Statement prepared or certified by
the independent accountants within the meaning of Sections 7 and 11 of the
Securities Act.

         In addition, the combined financial statements and related financial
statement schedule of the Henkel-Ecolab Joint Venture as of November 30, 1998
and for the year ended November 30, 1998, which

                                       2
are included in the Company's Annual Report on Form 10-K for the year ended
December 31, 1998, and incorporated by reference in this Registration
Statement, have been audited by PricewaterhouseCoopers Gesellschaft mit
beschrankter Haftung Wirtschaftsprufungsgesellschaft, independent
accountants. The combined financial statements and related financial
statement schedule audited by PricewaterhouseCoopers Gesellschaft mit
beschrankter Haftung Wirtschaftsprufungsgesellschaft have been incorporated
herein by reference in reliance on such firm's reports given upon their
authority as experts in accounting and auditing. To the extent that
PricewaterhouseCoopers Gesellschaft mit beschrankter Haftung
Wirtschaftsprufungsgesellschaft examines and reports on the financial
statements and financial statement schedules of the Henkel-Ecolab Joint
Venture issued at future dates, and consents to the use of their reports
thereon, such financial statements and financial statement schedules will
also be incorporated by reference in this Registration Statement in reliance
upon their reports and said authority.

         In addition, the combined balance sheets of the Henkel-Ecolab Joint
Venture as of November 30, 1997 and 1996, and the related combined statements
of income, equity and cash flows for each of the periods beginning December
1, 1996 and 1995 and ended November 30, 1997 and 1996, respectively, and
related financial statement schedule for the same periods (collectively, the
"1996 and 1997 Henkel-Ecolab Joint Venture Financials"), which are included
in the Company's Annual Report on Form 10-K for the year ended December 31,
1998, and incorporated by reference in this Registration Statement, have been
audited by KPMG Deutsche Treuhand-Gesellschaft Aktiengesellschaft
Wirtschaftsprufungsgesellschaft, independent accountants. The 1996 and 1997
Henkel-Ecolab Joint Venture Financials audited by KPMG Deutsche
Treuhand-Gesellschaft Aktiengesellschaft Wirtschaftsprufungsgesellschaft have
been incorporated herein by reference in reliance on such firm's reports
given upon their authority as experts in accounting and auditing.

ITEM 4. DESCRIPTION OF SECURITIES.

         Not applicable - the Company's Common Stock and Rights to be offered
pursuant to this Registration Statement have been registered under Section 12
of the Exchange Act as described in Item 3 of this Part II.

ITEM 5. INTERESTS OF NAMED EXPERTS AND COUNSEL.

         Not applicable.

ITEM 6. INDEMNIFICATION OF DIRECTORS AND OFFICERS.

         Subsection (a) of Section 145 of the General Corporation Law of
Delaware ("DGCL") empowers a corporation to indemnify any person who was or
is a party or is threatened to be made a party to any threatened, pending or
completed action, suit or proceeding, whether civil, criminal, administrative
or investigative (other than an action by or in the right of the
corporation), by reason of the fact that such person is or was a director,
officer, employee or agent of the corporation or is or was serving at the
request of the corporation as a director, officer, employee or agent of
another corporation or enterprise, against expenses (including attorneys'
fees), judgments, fines and amounts paid in settlement actually and
reasonably incurred by such person in connection with such action, suit or
proceeding if such person acted in good faith and in a manner such person
reasonably believed to be in or not opposed to the best interests of the
corporation, and with respect to any criminal action or proceeding, had no
reasonable cause to believe such person's conduct was unlawful.

         Subsection (b) of Section 145 empowers a corporation to indemnify
any person who was or is a party or threatened to be made a party to any
threatened, pending or completed action or suit by or in the right of the
corporation to procure a judgment in its favor by reason of the fact that
such person acted in any of the

                                       3
capacities set forth above, against expenses actually and reasonably incurred
by such person in connection with the defense or settlement of such action or
suit if such person acted under similar standards, except that no
indemnification may be made in respect of any claim, issue or matter as to
which such person shall have been adjudged to be liable to the corporation
unless and only to the extent that the Court of Chancery or the court in
which such action or suit was brought shall determine that, despite the
adjudication of liability, such person is fairly and reasonably entitled to
indemnity for such expenses which the court shall deem proper.

         Section 145 further provides that, to the extent a director or
officer of a corporation has been successful in the defense of any action,
suit or proceeding referred to in subsections (a) and (b) or in the defense
of any claim, issue or matter therein, such person shall be indemnified
against expenses (including attorneys' fees) actually and reasonably incurred
in connection therewith; that indemnification provided for by Section 145
shall not be deemed exclusive of any other rights to which the indemnified
party may be entitled; and that the scope of indemnification extends to
directors, officers, employees or agents of a constituent corporation
absorbed in a consolidation or merger and persons serving in that capacity at
the request of the constituent corporation for another. Section 145 also
empowers the corporation to purchase and maintain insurance on behalf of a
director or officer of the corporation against any liability asserted against
or incurred by such person in any such capacity or arising out of such
person's status as such, whether or not the corporation would have the power
to indemnify such person against such liabilities under Section 145,
including liabilities under the Securities Act.

         Article V of the Company's By-Laws provides for indemnification of
the Company's officers and directors to the full extent allowed by the DGCL.

         In addition, Article IV of the Company's Restated Certificate of
Incorporation provides that the Company's directors do not have personal
liability to the Company or its stockholders for monetary damages for any
breach of their fiduciary duty as directors, except (i) for a breach of the
duty of loyalty, (ii) for acts or omissions not in good faith or which
involve intentional misconduct or knowing violation of the law, (iii) for
willful or negligent violations of certain provisions under the DGCL imposing
certain requirements with respect to stock repurchases, redemptions and
dividends, or (iv) for any transaction from which the director derived an
improper personal benefit. Subject to these exceptions, under Article IV,
directors do not have any personal liability to the Company or its
stockholders for any violation of their fiduciary duty.

         The Company has directors and officers liability insurance which
protects each director or officer from certain claims and suits, including
stockholder derivative suits, even where the director may be determined to
not be entitled to indemnification under the DGCL and claims and suits
arising under the Securities Act. The policy may also afford coverage under
circumstances where the facts do not justify a finding that the director or
officer acted in good faith and in a manner that was in or not opposed to the
best interests of the Company.

         The Company has entered into indemnification agreements with each of
its directors (the "Indemnification Agreements"). The Indemnification
Agreements provide for the prompt indemnification "to the fullest extent
permitted by law" and for the prompt advancement of expenses, including
attorneys' fees and other costs, expenses and obligations paid or incurred in
connection with investigating, defending, being a witness or participating in
(including on appeal) any threatened, pending or completed action, suit or
proceeding related to the fact that such director is or was a director,
officer, employee, trustee, agent or fiduciary of the Company or is or was
serving at the request of the Company as a director, officer, employee,
trustee, agent or fiduciary of another corporation, partnership, joint
venture, employee benefit plan trust or other enterprise, or by reason of
anything done or not done by a director in any such capacity. The
Indemnification Agreements further provide that the Company has the burden of
proving that a director is not entitled to indemnification in any particular
case.

                                       4
The foregoing represents a summary of the general effect of the
DGCL, the Company's By-Laws and Restated Certificate of Incorporation, the
Company's directors and officers liability insurance coverage and the
Indemnification Agreements for purposes of general description only.

ITEM 7. EXEMPTION FROM REGISTRATION CLAIMED.

         Not applicable - no securities are to be re-offered or resold
pursuant to this Registration Statement.

ITEM 8.  EXHIBITS.
4.1      Restated Certificate of Incorporation of the Company (incorporated by
         reference to Exhibit (3) to the Company's Current Report on Form 8-K
         dated October 22, 1997 (File No. 1-9328)).
4.2      Bylaws of the Company, as amended through February 18, 1999
         (incorporated by reference to Exhibit (3)B to the Company's Annual
         Report on Form 10-K for the year ended December 31, 1998 (File No.
         1-9328)).
4.3      Form of Common Stock Certificate (incorporated by reference to Exhibit
         4(B) to the Company's Annual Report on Form 10-K for the year ended
         December 31, 1995 (File No. 1-9328)).
4.4      Rights Agreement, dated as of February 24, 1996, between the Company
         and First Chicago Trust Company of New York, as Rights Agent
         (incorporated by reference to Exhibit 4 to the Company's Current Report
         on Form 8-K dated February 24, 1996 (File No. 1-9328)).
15.1     Letter of PricewaterhouseCoopers LLP regarding unaudited interim
         financial information (filed herewith electronically).
23.1     Consent of PricewaterhouseCoopers LLP (filed herewith electronically).
23.2     Consent of PricewaterhouseCoopers GmbH (filed herewith electronically).
23.3     Consent of KPMG Deutsche Treuhand-Gesellschaft Aktiengesellschaft
         Wirtschaftsprufungsgesellschaft (filed herewith electronically).
24.1     Powers of Attorney (filed herewith electronically).
ITEM 9. UNDERTAKINGS.

(a)      The undersigned Registrant hereby undertakes:

         (1)      To file, during any period in which offers or sales are being
                  made, a post-effective amendment to this registration
                  statement:

                  (i)      To include any prospectus required by Section
                           10(a)(3) of the Securities Act;

                  (ii)     To reflect in the prospectus any facts or events
                           arising after the effective date of the registration
                           statement (or the most recent post-effective
                           amendment thereof) which, individually or in the
                           aggregate, represent a fundamental change in the
                           information set forth in the registration statement.
                           Notwithstanding the foregoing, any increase or
                           decrease in volume of securities offered (if the
                           total dollar value of securities offered would not
                           exceed that which was registered) and any deviation
                           from the low or high end of the estimated maximum
                           offering range may be reflected in the form of
                           prospectus filed with the Commission pursuant to Rule
                           424(b) under the Securities Act if, in the aggregate,
                           the changes in volume and price represent no more
                           than a 20% change in the maximum aggregate offering
                           price set forth in the "Calculation of Registration
                           Fee" table in the effective registration statement;

                  (iii)    To include any material information with respect to
                           the plan of distribution not

                                       5
previously disclosed in the registration statement or
                           any material change to such information in the
                           registration statement;

                  PROVIDED, HOWEVER, that paragraphs (a)(1)(i) and (a)(1)(ii) do
                  not apply if the information required to be included in a
                  post-effective amendment by those paragraphs is contained in
                  periodic reports filed with or furnished to the Commission by
                  the Registrant pursuant to Section 13 or Section 15(d) of the
                  Exchange Act that are incorporated by reference in the
                  registration statement.

         (2)      That, for the purpose of determining any liability under the
                  Securities Act, each such post-effective amendment shall be
                  deemed to be a new registration statement relating to the
                  securities offered therein, and the offering of such
                  securities at that time shall be deemed to be the initial bona
                  fide offering thereof.

         (3)      To remove from registration by means of a post-effective
                  amendment any of the securities being registered which remain
                  unsold at the termination of the offering.

(b)      The undersigned Registrant hereby undertakes that, for purposes of
         determining any liability under the Securities Act, each filing of the
         Registrant's annual report pursuant to Section 13(a) or Section 15(d)
         of the Exchange Act (and, where applicable, each filing of an employee
         benefit plan's annual report pursuant to Section 15(d) of the Exchange
         Act) that is incorporated by reference in the registration statement
         shall be deemed to be a new registration statement relating to the
         securities offered therein, and the offering of such securities at that
         time shall be deemed to be the initial bona fide offering thereof.

(c)      Insofar as indemnification for liabilities arising under the Securities
         Act may be permitted to directors, officers and controlling persons of
         the Registrant, the Registrant has been advised that in the opinion of
         the Commission such indemnification is against public policy as
         expressed in the Securities Act and is, therefore, unenforceable. In
         the event that a claim for indemnification against such liabilities
         (other than the payment by the Registrant of expenses incurred or paid
         by a director, officer or controlling person of the Registrant in the
         successful defense of any action, suit or proceeding) is asserted by
         such director, officer or controlling person in connection with the
         securities being registered, the Registrant will, unless in the opinion
         of its counsel the matter has been settled by controlling precedent,
         submit to a court of appropriate jurisdiction the question whether such
         indemnification by it is against public policy as expressed in the
         Securities Act and will be governed by the final adjudication of such
         issue.

                                       6
SIGNATURES

THE REGISTRANT. Pursuant to the requirements of the Securities Act of 1933,
the Registrant certifies that it has reasonable grounds to believe that it
meets all of the requirements for filing on Form S-8 and has duly caused this
registration statement to be signed on its behalf by the undersigned,
thereunto duly authorized, in the City of St. Paul, State of Minnesota, on
January 20, 2000.

                                 ECOLAB INC.

                                By: /s/ Allan L. Schuman
                                    ----------------------------------------
                                    Allan L. Schuman
                                    Chairman of the Board, President and Chief
                                    Executive Officer

         Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed on January 20, 2000 by the following
persons in the capacities indicated.

/s/ Allan L. Schuman                   Chairman of the Board, President
----------------------------------     and Chief Executive Officer (Principal
Allan L. Schuman                       Executive Officer) and Director

/s/ L. White Matthews, III             Executive Vice President and Chief
----------------------------------     Financial Officer (Principal Financial
L. White Matthews, III                 Officer) and Director

/s/ Steven L. Fritze                   Vice President and Controller (Principal
----------------------------------     Accounting Officer)
Steven L. Fritze

/s/ Kenneth A. Iverson                 Directors
----------------------------------
Kenneth A. Iverson, as attorney-in-
fact for Les S. Biller, Ruth S. Block,
Jerry A. Grundhofer, James J. Howard,
William L. Jews, Joel W. Johnson,
Jerry W. Levin, Robert L. Lumpkins,
Richard L. Schall, Roland Schulz,
Hugo Uyterhoeven and Albrecht Woeste

Director not signing:  Reuben F. Richards

                                       7
INDEX TO EXHIBITS
ITEM                 DESCRIPTION                                               METHOD OF FILING
NO.                  -----------                                               ----------------
-----
4.1     Restated Certificate of Incorporation of                   Incorporated by reference to Exhibit (3) to
        the Company.........................................       the Company's Current Report on Form 8-K
                                                                   dated October 22, 1997 (File No. 1-9328).

4.2     Bylaws of the Company, as amended                          Incorporated by reference to Exhibit (3)B
        through February 18, 1999...........................       to the Company's Annual Report on Form 10-K
                                                                   for the year ended December 31 1998 (File
                                                                   No. 1-9328).

4.3     Form of Common Stock Certificate....................       Incorporated by reference to Exhibit
                                                                   4(B) to the Company's Annual Report on Form
                                                                   10-K for the year ended December 31, 1995
                                                                   (File No. 1-9328).

4.4     Rights Agreement, dated as of February                     Incorporated by reference to Exhibit 4 to
        24, 1996, between the Company and                          the Company's Current Report on Form 8-K
        First Chicago Trust Company of New                         dated February 24, 1996 (File No. 1-9328).
        York, as Rights Agent...............................

15.1    Letter of PricewaterhouseCoopers LLP regarding
        unaudited interim financial information.                   Filed herewith electronically.

23.1    Consent of PricewaterhouseCoopers LLP.                     Filed herewith electronically.

23.2    Consent of PricewaterhouseCoopers GmbH.                    Filed herewith electronically.

23.3    Consent of KPMG Deutsche Treuhand -                        Filed herewith electronically.
        Gesellschaft Aktiengesellschaft
        Wirtschaftsprufungsgesellschaft.....................

24.1    Powers of Attorney..................................       Filed herewith electronically.
8