<PAGE>

 As filed with the Securities and Exchange Commission on September 12, 1997
                                                           Registration No. 333-
--------------------------------------------------------------------------------

                          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
                                    (612) 293-2233
                 (Address, including zip code, and telephone number,
               including area code, of registrant's principal executive
                                       offices)

                                ______________________
                                     1995 ECOLAB
                                STOCK RECOGNITION PLAN
                               (Full title of the plan)

                                ______________________
                              WILLIAM R. ROSENGREN, ESQ.
                            SENIOR VICE PRESIDENT-LAW AND
                                   GENERAL COUNSEL
                                     ECOLAB INC.
                                    ECOLAB CENTER
                               370 NORTH WABASHA STREET
                              ST. PAUL, MINNESOTA 55102
                                    (612) 293-2233
                 (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(1)   Offering Price per Share(2)   Aggregate Offering Price(2)  Registration Fee
----------------------------------------------------------------------------------------------------------------------------------
<S>                                   <C>              <C>                           <C>                          <C>
Common Stock, par value 
$1.00 per share(3). . . . . . .       88,530 shares         $47.5625                     $4,210,708.10               $1,275.98
----------------------------------------------------------------------------------------------------------------------------------
</TABLE>

(1) In addition, pursuant to Rule 416 under the Securities Act of 1933, as
    amended, this Registration Statement includes an indeterminate number of
    additional shares as may be issuable as a result of anti-dilution
    provisions described in the 1995 Ecolab Stock Recognition Plan.

(2) 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, on the basis of the average between the high and low reported
    sale prices of the Registrant's Common Stock on September 9, 1997, as
    reported on the New York Stock Exchange.

(3) Each share of Common Stock includes one 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, 1996; (2) Quarterly
Reports on Form 10-Q for the quarters ended March 31 and June 30, 1997; (3)
Current Reports on Forms 8-K dated August 15, 1997, August 22, 1997 and August
29, 1997; (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, 1996; and (5) the description of the Company's Common
Stock, Preferred Stock and Rights contained in its Registration Statement on
Form 8-A, including any amendments or reports filed for the purpose of updating
such description.

    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, 1996, and
incorporated by reference in this Registration Statement, have been audited by
Coopers & Lybrand L.L.P., independent accountants, for the periods indicated in
such firm's reports thereon.  The consolidated financial statements and
financial statement schedule audited by Coopers & Lybrand L.L.P. 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
Coopers & Lybrand L.L.P. 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 the
Registration Statement in reliance upon their reports and said authority.

    With respect to unaudited interim financial information incorporated by
reference in this Registration Statement, the independent accountants have
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 of 1933 (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 financial statement
schedule of the 

                                       2
<PAGE>

Henkel-Ecolab Joint Venture, which are included in the Company's Annual 
Report on Form 10-K for the year ended December 31, 1996, and incorporated by 
reference in this Registration Statement, have been audited by KPMG Deutsche 
Treuhand-Gesellschaft Aktiengesellschaft, independent accountants, for the 
periods indicated in such firm's reports thereon.  The combined financial 
statements and financial statement schedule audited by KPMG Deutsche 
Treuhand-Gesellschaft Aktiengesellschaft 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 KPMG Deutsche 
Treuhand-Gesellschaft Aktiengesellschaft examines and reports on the 
financial statements and the 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 the Registration 
Statement in reliance upon their reports and said authority.

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 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 

                                       3
<PAGE>

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 Delaware law.

    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.

    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.

                                       4
<PAGE>

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>
<CAPTION>

<S>      <C>
4.1      Restated Certificate of Incorporation of the Company (incorporated by
         reference to Exhibit (3) B to the Company's Annual Report on Form 10-K 
         for the year ended December 31, 1996 (File No. 1-9328)).
4.2      Bylaws of the Company, as amended through December 16, 1996 
         (incorporated by reference to  Exhibit 3 to the Company's Current 
         Report on Form 8-K dated December 16, 1996 (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 Coopers & Lybrand L.L.P. regarding unaudited interim financial
         information (filed herewith electronically).
23.1     Consent of Coopers & Lybrand L.L.P. (filed herewith electronically).
23.2     Consent of KPMG Deutsche Treuhand-Gesellschaft Aktiengesellschaft (filed
         herewith electronically).
24.1     Powers of Attorney (filed herewith electronically).
          
</TABLE>

ITEM 9.  UNDERTAKINGS.

    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 of 1933;
               
         (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 of 1933 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 (1)(i) and (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 Securities Exchange Act of 1934
         that are incorporated by reference in the registration statement.
          
    (2)  That, for the purpose of determining any liability under the
         Securities Act of 1933, 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.
          
    The undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act of 1933, each filing of the
Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Securities Exchange Act of 1934 (and, where applicable, each filing of an
employee benefit plan's annual report pursuant to Section 15(d) of the
Securities Exchange Act of 1934) 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.

    Insofar as indemnification for liabilities arising under the Securities Act
of 1933 may be permitted to directors, officers and controlling persons of the
Registrant, the Registrant has been advised that in the opinion of the
Securities and Exchange Commission such indemnification is against public policy
as expressed in the Securities Act of 1933 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 Act and
will be governed by the final adjudication of such issue.

                                       6
<PAGE>

                                      SIGNATURES

    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 September 12, 1997.

                                  ECOLAB INC.


                                  By: /s/ Allan L. Schuman
                                     -----------------------------------------
                                      Allan L. Schuman 
                                      President and Chief Executive Officer

    Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed on September 12, 1997 by the following
persons in the capacities indicated. 


/s/ Allan L. Schuman            President and Chief Executive Officer (Principal
------------------------------
Allan L. Schuman                Executive Officer) and Director




/s/ Michael E. Shannon          Chairman of the Board, Chief Financial and
------------------------------
Michael E. Shannon              Administrative Officer (Principal Financial 
                                Officer) and Director

/s/ Arthur E. Henningsen, Jr.   Senior Vice President and Controller (Principal
------------------------------
Arthur E. Henningsen, Jr.       Accounting Officer)



/s/ Kenneth A. Iverson          Directors
------------------------------
Kenneth A. Iverson, as
attorney-in-fact for Ruth S. 
Block, James J. Howard, Joel W.
Johnson, Jerry W. Levin, Roland 
Schulz, Philip L. Smith, Hugo 
Uyterhoeven and Albrecht Woeste 

Directors not signing:   Reuben F. Richards, Richard L. Schall and
                         Leslie S. Biller

                                       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 
         the Company.........................................  (3) B to the Company's Annual Report 
                                                               on Form 10-K for the year ended
                                                               December 31, 1996 (File No. 1-9328).

4.2      Bylaws of the Company, as amended                     Incorporated by reference to Exhibit 3 
         through December 16, 1996...........................  to the Company's Current Report on
                                                               Form 8-K dated December 16, 1996 
                                                               (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 
         24, 1996, between the Company and                     to the Company's Current Report on 
         First Chicago Trust Company of New                    Form 8-K dated February 24, 1996.
         York, as Rights Agent...............................  

15.1     Letter of Coopers & Lybrand L.L.P.                    Filed herewith electronically.
         regarding unaudited interim financial
         information.........................................  

23.1     Consent of Coopers & Lybrand L.L.P..................  Filed herewith electronically.

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

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

</TABLE>
                                       8
[{"type": "S-8", "sequence": "1", "description": "S-8 COV", "secsgml_size_bytes": 26821}]
{"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": "333-35519", "film-number": "97679613"}, "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 September 12, 1997
                                                           Registration No. 333-
--------------------------------------------------------------------------------

                          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
                                    (612) 293-2233
                 (Address, including zip code, and telephone number,
               including area code, of registrant's principal executive
                                       offices)

                                ______________________
                                     1995 ECOLAB
                                STOCK RECOGNITION PLAN
                               (Full title of the plan)

                                ______________________
                              WILLIAM R. ROSENGREN, ESQ.
                            SENIOR VICE PRESIDENT-LAW AND
                                   GENERAL COUNSEL
                                     ECOLAB INC.
                                    ECOLAB CENTER
                               370 NORTH WABASHA STREET
                              ST. PAUL, MINNESOTA 55102
                                    (612) 293-2233
                 (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(1)   Offering Price per Share(2)   Aggregate Offering Price(2)  Registration Fee
----------------------------------------------------------------------------------------------------------------------------------
Common Stock, par value 
$1.00 per share(3). . . . . . .       88,530 shares         $47.5625                     $4,210,708.10               $1,275.98
----------------------------------------------------------------------------------------------------------------------------------
(1) In addition, pursuant to Rule 416 under the Securities Act of 1933, as
    amended, this Registration Statement includes an indeterminate number of
    additional shares as may be issuable as a result of anti-dilution
    provisions described in the 1995 Ecolab Stock Recognition Plan.

(2) 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, on the basis of the average between the high and low reported
    sale prices of the Registrant's Common Stock on September 9, 1997, as
    reported on the New York Stock Exchange.

(3) Each share of Common Stock includes one 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, 1996; (2) Quarterly
Reports on Form 10-Q for the quarters ended March 31 and June 30, 1997; (3)
Current Reports on Forms 8-K dated August 15, 1997, August 22, 1997 and August
29, 1997; (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, 1996; and (5) the description of the Company's Common
Stock, Preferred Stock and Rights contained in its Registration Statement on
Form 8-A, including any amendments or reports filed for the purpose of updating
such description.

    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, 1996, and
incorporated by reference in this Registration Statement, have been audited by
Coopers & Lybrand L.L.P., independent accountants, for the periods indicated in
such firm's reports thereon.  The consolidated financial statements and
financial statement schedule audited by Coopers & Lybrand L.L.P. 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
Coopers & Lybrand L.L.P. 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 the
Registration Statement in reliance upon their reports and said authority.

    With respect to unaudited interim financial information incorporated by
reference in this Registration Statement, the independent accountants have
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 of 1933 (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 financial statement
schedule of the 

                                       2
Henkel-Ecolab Joint Venture, which are included in the Company's Annual 
Report on Form 10-K for the year ended December 31, 1996, and incorporated by 
reference in this Registration Statement, have been audited by KPMG Deutsche 
Treuhand-Gesellschaft Aktiengesellschaft, independent accountants, for the 
periods indicated in such firm's reports thereon.  The combined financial 
statements and financial statement schedule audited by KPMG Deutsche 
Treuhand-Gesellschaft Aktiengesellschaft 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 KPMG Deutsche 
Treuhand-Gesellschaft Aktiengesellschaft examines and reports on the 
financial statements and the 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 the Registration 
Statement in reliance upon their reports and said authority.

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 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 

                                       3
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 Delaware law.

    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.

    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.

                                       4
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) B to the Company's Annual Report on Form 10-K 
         for the year ended December 31, 1996 (File No. 1-9328)).
4.2      Bylaws of the Company, as amended through December 16, 1996 
         (incorporated by reference to  Exhibit 3 to the Company's Current 
         Report on Form 8-K dated December 16, 1996 (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 Coopers & Lybrand L.L.P. regarding unaudited interim financial
         information (filed herewith electronically).
23.1     Consent of Coopers & Lybrand L.L.P. (filed herewith electronically).
23.2     Consent of KPMG Deutsche Treuhand-Gesellschaft Aktiengesellschaft (filed
         herewith electronically).
24.1     Powers of Attorney (filed herewith electronically).
ITEM 9.  UNDERTAKINGS.

    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 of 1933;
               
         (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 of 1933 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 (1)(i) and (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 Securities Exchange Act of 1934
         that are incorporated by reference in the registration statement.
          
    (2)  That, for the purpose of determining any liability under the
         Securities Act of 1933, 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.
          
    The undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act of 1933, each filing of the
Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Securities Exchange Act of 1934 (and, where applicable, each filing of an
employee benefit plan's annual report pursuant to Section 15(d) of the
Securities Exchange Act of 1934) 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.

    Insofar as indemnification for liabilities arising under the Securities Act
of 1933 may be permitted to directors, officers and controlling persons of the
Registrant, the Registrant has been advised that in the opinion of the
Securities and Exchange Commission such indemnification is against public policy
as expressed in the Securities Act of 1933 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 Act and
will be governed by the final adjudication of such issue.

                                       6
SIGNATURES

    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 September 12, 1997.

                                  ECOLAB INC.

                                  By: /s/ Allan L. Schuman
                                     -----------------------------------------
                                      Allan L. Schuman 
                                      President and Chief Executive Officer

    Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed on September 12, 1997 by the following
persons in the capacities indicated. 

/s/ Allan L. Schuman            President and Chief Executive Officer (Principal
------------------------------
Allan L. Schuman                Executive Officer) and Director

/s/ Michael E. Shannon          Chairman of the Board, Chief Financial and
------------------------------
Michael E. Shannon              Administrative Officer (Principal Financial 
                                Officer) and Director

/s/ Arthur E. Henningsen, Jr.   Senior Vice President and Controller (Principal
------------------------------
Arthur E. Henningsen, Jr.       Accounting Officer)

/s/ Kenneth A. Iverson          Directors
------------------------------
Kenneth A. Iverson, as
attorney-in-fact for Ruth S. 
Block, James J. Howard, Joel W.
Johnson, Jerry W. Levin, Roland 
Schulz, Philip L. Smith, Hugo 
Uyterhoeven and Albrecht Woeste 

Directors not signing:   Reuben F. Richards, Richard L. Schall and
                         Leslie S. Biller

                                       7
INDEX TO EXHIBITS
Item                    Description                                 Method of Filing
No.                     -----------                                 ----------------
--
4.1      Restated Certificate of Incorporation of              Incorporated by reference to Exhibit 
         the Company.........................................  (3) B to the Company's Annual Report 
                                                               on Form 10-K for the year ended
                                                               December 31, 1996 (File No. 1-9328).

4.2      Bylaws of the Company, as amended                     Incorporated by reference to Exhibit 3 
         through December 16, 1996...........................  to the Company's Current Report on
                                                               Form 8-K dated December 16, 1996 
                                                               (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 
         24, 1996, between the Company and                     to the Company's Current Report on 
         First Chicago Trust Company of New                    Form 8-K dated February 24, 1996.
         York, as Rights Agent...............................  

15.1     Letter of Coopers & Lybrand L.L.P.                    Filed herewith electronically.
         regarding unaudited interim financial
         information.........................................  

23.1     Consent of Coopers & Lybrand L.L.P..................  Filed herewith electronically.

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

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