As filed with the Securities and Exchange Commission on April 25, 2000
                                                             File No. 333-_____


                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                             ----------------------

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

                            SOUTHWEST GAS CORPORATION
             (Exact name of Registrant as specified in its charter)








                  California                              88-0085720
        (State or other jurisdiction of                (I.R.S. Employer
        incorporation or organization)               Identification Number)

           5241 Spring Mountain Road
                P.O. Box 98510
               Las Vegas, Nevada                            89193-8510
    (Address of principal executive offices)                (Zip Code)

              SOUTHWEST GAS CORPORATION EMPLOYEES' INVESTMENT PLAN
                            (Full title of the plan)

                                GEORGE C. BIEHL
      Senior Vice President/Chief Financial Officer & Corporate Secretary
                           Southwest Gas Corporation
                           5241 Spring Mountain Road
                                P.O. Box 98510
                          Las Vegas, Nevada 89193-8510
                     (Name and address of agent for service)

                                (702) 876-7237
          (Telephone number, including area code, of agent for service)

<TABLE>
                         CALCULATION OF REGISTRATION FEE
--------------------------------------- ----------------- --------------------- --------------------- --------------
<CAPTION>

                                             Amount         Proposed maximum      Proposed maximum      Amount of
                                             to be         offering price per        aggregate        registration
 Title of securities being registered      registered          share (3)         offering price (3)        fee
                                             (1)(2)
--------------------------------------- ----------------- --------------------- --------------------- --------------
<S>          <C>                         <C>                    <C>                  <C>               <C>
Common Stock ($1 par value).......       400,000 shares         $18.8125             $7,525,000        $1,986.60

======================================= ================= ===================== ===================== ==============
</TABLE>

(1) In addition, pursuant to Rule 416(c) under the Securities Act of 1933, this
    Registration Statement also covers an indeterminate amount of interests to
    be offered or sold pursuant to the employee benefit plan described herein.

(2) The shares of common stock being registered consist of shares to be acquired
    by the Trustee pursuant to the plan for the account of participants. Each
    share is accompanied by a common share purchase right pursuant to the
    Registrant's Rights Agreement, dated February 9, 1999, as amended, with
    Harris Trust Company, as Rights Agent.

(3) Pursuant to Rule 457(h), the maximum offering price, per share and in the
    aggregate, and the registration fee were calculated based upon the average
    of the high and low composite prices of the Common Stock as reported by the
    Consolidated Tape Association on April 20, 2000 of $18.8125.

As permitted by Rule 429, the Prospectus with respect to this Registration
Statement also relates to Registrant's Registration Statement on Form S-8
(333-31267).


<PAGE>

                                     PART I

              INFORMATION REQUIRED IN THE SECTION 10(A) PROSPECTUS

Item 1.  Plan Information*

Item 2.  Registrant Information and Employee Plan Annual Information*

         *   Information required by Part I to be contained in the Section 10(a)
             prospectus is omitted from the Registration Statement in accordance
             with Rule 428 under the Securities Act of 1933 and the Note to Part
             I of Form S-8.


                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.  Incorporation of Certain Documents by Reference

         The following documents of Southwest Gas Corporation (the "Company")
filed with the Securities and Exchange Commission are incorporated herein by
reference:

         (a)  Annual Report on Form 10-K for the Company's fiscal year ended
              December 31, 1999 and the Southwest Gas Corporation Employees'
              Investment Plan Annual Report on Form 11-K for the year ended
              December 31, 1998;

         (b)  Description of the Company's Common Stock contained in its
              Registration Statement on Form 8-A filed on June 8, 1979, and any
              amendment or report filed for the purpose of updating such
              description.

         All documents subsequently filed by the Company pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934, as amended
(the "Exchange Act"), prior to the filing of a post-effective amendment which
indicates that all securities offered have been sold or which deregisters all
securities 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. Any statement contained herein or in a document,
all or a portion of which is incorporated or deemed to be incorporated by
reference herein, shall be deemed to be modified or superseded for purposes of
this Registration Statement to the extent that a statement contained herein or
in any other subsequently filed document which also is or is deemed to be
incorporated by reference herein modifies or supersedes such statement. Any such
statement so modified or superseded shall not be deemed, except as so modified
or amended, to constitute a part of this Registration Statement.

Item 4.  Description of Securities

         The Company's Common Stock, $1.00 par value, (the "Common Stock") is
registered pursuant to Section 12 of the Exchange Act, and, therefore, the
description of securities is omitted.

                                      S-1
<PAGE>


Item 5.  Interests of Named Experts and Counsel

         Robert M. Johnson, Esq., as Assistant General Counsel for the Company,
has given an opinion to the Securities and Exchange Commission upon the validity
of the shares of Common Stock registered.

         The financial statements incorporated by reference in this Registration
Statement have been audited by Arthur Andersen LLP, independent public
accountants, as indicated in their report incorporated by reference in the
Company's Form 10-K for the year ended December 31, 1999, and their report
included in the Southwest Gas Corporation Employees' Investment Plan Annual
Report on Form 11-K for the year ended December 31, 1998, and are included
herein in reliance upon the authority of said firm as experts in accounting and
auditing in giving said reports.

Item 6.  Indemnification of Directors and Officers

         The Company's Articles of Incorporation contain a provision which
eliminates the liability of directors for monetary damages to the fullest extent
permissible under California law. The General Corporation Law of California (the
"Law") (i) authorizes the elimination of liability of directors for monetary
damages in an action brought by a shareholder in the right of the Company
(referred to herein as a "derivative action") or by the Company for breach of a
director's duties to the Company and its shareholders and (ii) authorizes the
Company to indemnify directors and officers for monetary damages for all acts or
omissions committed by them in their respective capacities; provided, however,
that liability is not limited nor may indemnification be provided for (a) acts
or omissions that involve intentional misconduct or knowing and culpable
violation of law, (b) for acts or omissions that a director or officer believes
to be contrary to the best interests of the Company or its shareholders or that
involve the absence of good faith on the part of a director or officer seeking
indemnification, (c) for any transaction from which a director or officer
derives an improper personal benefit, (d) for acts or omissions that show a
reckless disregard for the director's or officer's duty to the Company or its
shareholders in circumstances in which such person was aware, or should have
been aware, in the ordinary course of performing his or her duties, of a risk of
serious injury to the Company or its shareholders, (e) for acts or omissions
that constitute an unexcused pattern of inattention that amounts to an
abdication of the director's or officer's duty to the Company or its
shareholders, and (f) for liabilities arising under Section 310 (contracts in
which a director has a material financial interest) and Section 316 (certain
unlawful dividends, distributions, loans and guarantees) of the Law. In
addition, the Company may not indemnify directors and officers in circumstances
in which indemnification is expressly prohibited by Section 317 of the Law.

         The bylaws of the Company provide that the Company has the power to
indemnify directors and officers to the fullest extent permitted under
California law and the Company's Articles of Incorporation. The Company has
entered into indemnification agreements with its directors and officers which
require that the Company indemnify such directors and officers in all cases to
the fullest extent permitted by applicable provisions of the Law. The Company
also maintains a directors' and officers' liability insurance policy insuring
directors and officers of the Company for covered losses as defined in the
policy.

Item 7.  Exemption from Registration Claimed

         Not applicable.

Item 8.  Exhibits

       5.1  Opinion of Counsel of Southwest regarding legality of the securities
            to be registered
      23.1  Consent of Arthur Andersen LLP
      23.2  Consent of Counsel of Southwest (included in opinion filed as
            Exhibit 5.1 to this Registration Statement)
      24.1  Powers of Attorney
----------

                                      S-2
<PAGE>


         In lieu of the opinion of counsel or determination letter contemplated
by Item 601(b)(5) of Regulation S-K, Registrant hereby confirms that it has
submitted the Plan and undertakes that it will submit all amendments thereto to
the Internal Revenue Service (IRS) in a timely manner, and that it has made or
will make all changes required by the IRS in order to qualify the Plan under
Section 401 of the Internal Revenue Code.

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, unless the information required to be included
         in such post-effective amendment is contained in a periodic report
         filed by Registrant pursuant to Section 13 or Section 15(d) of the
         Securities Exchange Act of 1934 and incorporated herein by reference;

            (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 this Registration Statement, unless the information required to be
         included in such post-effective amendment is contained in a periodic
         report filed by Registrant pursuant to Section 13 or Section 15(d) of
         the Securities Exchange Act of 1934 and incorporated herein by
         reference;

           (iii) To include any material information with respect to the plan of
         distribution not previously disclosed in this Registration Statement or
         any material change to such information in this 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 further 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 each filing of the annual report of the
Plan 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 pursuant to the foregoing provisions, or otherwise, 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 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 Act and will be governed by the final adjudication of
such issue.

                                      S-3
<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 Las Vegas, State of Nevada, on April 21, 2000.


                                     SOUTHWEST GAS CORPORATION

                              By        /s/ MICHAEL O. MAFFIE
                                -------------------------------------
                                          Michael O. Maffie
                                President and Chief Executive Officer

                                   SIGNATURES


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


     Signature                         Title                          Date
     ---------                         -----                          ----

 /s/ MICHAEL O. MAFFIE         Director, President and            April 21, 2000
-------------------------      Chief Executive Officer
    (Michael O. Maffie)     (Principal Executive Officer)


 /s/ GEORGE C. BIEHL        Director, Senior Vice President,      April 21, 2000
-------------------------     Chief Financial Officer and
    (George C. Biehl)             Corporate Secretary
                             (Principal Financial Officer)


 /s/ EDWARD A. JANOV        Vice President, Controller and        April 21, 2000
-------------------------      Chief Accounting Officer
    (Edward A. Janov)       (Principal Accounting Officer)


 /s/ MANUEL J. CORTEZ *               Director                    April 21, 2000
-------------------------
    (Manuel J. Cortez)


 /s/ LLOYD T. DYER *                  Director                    April 21, 2000
-------------------------
    (Lloyd T. Dyer)


 /s/ THOMAS Y. HARTLEY *         Chairman of the Board            April 21, 2000
-------------------------             of Directors
    (Thomas Y. Hartley)


 /s/ MICHAEL B. JAGER *               Director                    April 21, 2000
-------------------------
    (Michael B. Jager)


                                      S-4
<PAGE>


     Signature                         Title                          Date
     ---------                         -----                          ----

 /s/ LEONARD R. JUDD *                Director                    April 21, 2000
-------------------------
    (Leonard R. Judd)


 /s/ JAMES J. KROPID *                Director                    April 21, 2000
-------------------------
    (James J. Kropid)


 /s/ CAROLYN M. SPARKS *              Director                    April 21, 2000
-------------------------
    (Carolyn M. Sparks)


 /s/ ROBERT S. SUNDT *                Director                    April 21, 2000
-------------------------
    (Robert S. Sundt)


 /s/ TERRANCE L. WRIGHT *             Director                    April 21, 2000
-------------------------
    (Terrance L. Wright)



*  By      /s/ GEORGE C. BIEHL
      --------------------------
              (George C. Biehl)
               Attorney-in-fact












                                      S-5

<PAGE>


                                    The Plan

       Pursuant to the requirements of the Securities Act of 1933, the Southwest
Gas Corporation Employees' Investment Plan Committee has duly caused this
Registration Statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of Las Vegas, State of Nevada, on April 21, 2000.


                            SOUTHWEST GAS CORPORATION
                           EMPLOYEES' INVESTMENT PLAN
                                    COMMITTEE


                               /s/ GEORGE C. BIEHL
                            ------------------------
                                (George C. Biehl)


                                /s/ JAMES P. KANE
                            ------------------------
                                 (James P. Kane)


                                /s/ FRED W. COVER
                            ------------------------
                                 (Fred W. Cover)


                              /s/ THOMAS R. SHEETS
                            ------------------------
                               (Thomas R. Sheets)











                                      S-6


<PAGE>

                                  Exhibit Index

  Exhibit
  Number                              Description
 ---------         -----------------------------------------------------

    5.1            Opinion of Counsel of the Company regarding legality of the
                   securities to be registered

   23.1            Consent of Arthur Andersen LLP

   23.2            Consent of Counsel of the Company (included in opinion filed
                   as Exhibit 5.1 to this Registration Statement)

   24.1            Powers of Attorney
[{"type": "S-8", "sequence": "1", "description": "FORM S-8 REGISTRATION STATEMENT", "secsgml_size_bytes": 19955}]
{"company-data": {"conformed-name": "SOUTHWEST GAS CORP", "cik": "0000092416", "assigned-sic": "4923", "irs-number": "880085720", "state-of-incorporation": "CA", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-35556", "film-number": "608318"}, "business-address": {"street1": "5241 SPRING MOUNTAIN RD", "street2": "PO BOX 98510", "city": "LAS VEGAS", "state": "NV", "zip": "89193-8510", "phone": "7028767237"}, "mail-address": {"street1": "5241 SPRING MOUNTAIN RD", "street2": "PO BOX 98510", "city": "LAS VEGAS", "state": "NV", "zip": "89193"}}
As filed with the Securities and Exchange Commission on April 25, 2000
                                                             File No. 333-_____

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                             ----------------------

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

                            SOUTHWEST GAS CORPORATION
             (Exact name of Registrant as specified in its charter)

                  California                              88-0085720
        (State or other jurisdiction of                (I.R.S. Employer
        incorporation or organization)               Identification Number)

           5241 Spring Mountain Road
                P.O. Box 98510
               Las Vegas, Nevada                            89193-8510
    (Address of principal executive offices)                (Zip Code)

              SOUTHWEST GAS CORPORATION EMPLOYEES' INVESTMENT PLAN
                            (Full title of the plan)

                                GEORGE C. BIEHL
      Senior Vice President/Chief Financial Officer & Corporate Secretary
                           Southwest Gas Corporation
                           5241 Spring Mountain Road
                                P.O. Box 98510
                          Las Vegas, Nevada 89193-8510
                     (Name and address of agent for service)

                                (702) 876-7237
          (Telephone number, including area code, of agent for service)

                         CALCULATION OF REGISTRATION FEE
--------------------------------------- ----------------- --------------------- --------------------- --------------
Amount         Proposed maximum      Proposed maximum      Amount of
                                             to be         offering price per        aggregate        registration
 Title of securities being registered      registered          share (3)         offering price (3)        fee
                                             (1)(2)
--------------------------------------- ----------------- --------------------- --------------------- --------------
Common Stock ($1 par value).......       400,000 shares         $18.8125             $7,525,000        $1,986.60

======================================= ================= ===================== ===================== ==============
(1) In addition, pursuant to Rule 416(c) under the Securities Act of 1933, this
    Registration Statement also covers an indeterminate amount of interests to
    be offered or sold pursuant to the employee benefit plan described herein.

(2) The shares of common stock being registered consist of shares to be acquired
    by the Trustee pursuant to the plan for the account of participants. Each
    share is accompanied by a common share purchase right pursuant to the
    Registrant's Rights Agreement, dated February 9, 1999, as amended, with
    Harris Trust Company, as Rights Agent.

(3) Pursuant to Rule 457(h), the maximum offering price, per share and in the
    aggregate, and the registration fee were calculated based upon the average
    of the high and low composite prices of the Common Stock as reported by the
    Consolidated Tape Association on April 20, 2000 of $18.8125.

As permitted by Rule 429, the Prospectus with respect to this Registration
Statement also relates to Registrant's Registration Statement on Form S-8
(333-31267).
PART I

              INFORMATION REQUIRED IN THE SECTION 10(A) PROSPECTUS

Item 1.  Plan Information*

Item 2.  Registrant Information and Employee Plan Annual Information*

         *   Information required by Part I to be contained in the Section 10(a)
             prospectus is omitted from the Registration Statement in accordance
             with Rule 428 under the Securities Act of 1933 and the Note to Part
             I of Form S-8.

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.  Incorporation of Certain Documents by Reference

         The following documents of Southwest Gas Corporation (the "Company")
filed with the Securities and Exchange Commission are incorporated herein by
reference:

         (a)  Annual Report on Form 10-K for the Company's fiscal year ended
              December 31, 1999 and the Southwest Gas Corporation Employees'
              Investment Plan Annual Report on Form 11-K for the year ended
              December 31, 1998;

         (b)  Description of the Company's Common Stock contained in its
              Registration Statement on Form 8-A filed on June 8, 1979, and any
              amendment or report filed for the purpose of updating such
              description.

         All documents subsequently filed by the Company pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934, as amended
(the "Exchange Act"), prior to the filing of a post-effective amendment which
indicates that all securities offered have been sold or which deregisters all
securities 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. Any statement contained herein or in a document,
all or a portion of which is incorporated or deemed to be incorporated by
reference herein, shall be deemed to be modified or superseded for purposes of
this Registration Statement to the extent that a statement contained herein or
in any other subsequently filed document which also is or is deemed to be
incorporated by reference herein modifies or supersedes such statement. Any such
statement so modified or superseded shall not be deemed, except as so modified
or amended, to constitute a part of this Registration Statement.

Item 4.  Description of Securities

         The Company's Common Stock, $1.00 par value, (the "Common Stock") is
registered pursuant to Section 12 of the Exchange Act, and, therefore, the
description of securities is omitted.

                                      S-1
Item 5.  Interests of Named Experts and Counsel

         Robert M. Johnson, Esq., as Assistant General Counsel for the Company,
has given an opinion to the Securities and Exchange Commission upon the validity
of the shares of Common Stock registered.

         The financial statements incorporated by reference in this Registration
Statement have been audited by Arthur Andersen LLP, independent public
accountants, as indicated in their report incorporated by reference in the
Company's Form 10-K for the year ended December 31, 1999, and their report
included in the Southwest Gas Corporation Employees' Investment Plan Annual
Report on Form 11-K for the year ended December 31, 1998, and are included
herein in reliance upon the authority of said firm as experts in accounting and
auditing in giving said reports.

Item 6.  Indemnification of Directors and Officers

         The Company's Articles of Incorporation contain a provision which
eliminates the liability of directors for monetary damages to the fullest extent
permissible under California law. The General Corporation Law of California (the
"Law") (i) authorizes the elimination of liability of directors for monetary
damages in an action brought by a shareholder in the right of the Company
(referred to herein as a "derivative action") or by the Company for breach of a
director's duties to the Company and its shareholders and (ii) authorizes the
Company to indemnify directors and officers for monetary damages for all acts or
omissions committed by them in their respective capacities; provided, however,
that liability is not limited nor may indemnification be provided for (a) acts
or omissions that involve intentional misconduct or knowing and culpable
violation of law, (b) for acts or omissions that a director or officer believes
to be contrary to the best interests of the Company or its shareholders or that
involve the absence of good faith on the part of a director or officer seeking
indemnification, (c) for any transaction from which a director or officer
derives an improper personal benefit, (d) for acts or omissions that show a
reckless disregard for the director's or officer's duty to the Company or its
shareholders in circumstances in which such person was aware, or should have
been aware, in the ordinary course of performing his or her duties, of a risk of
serious injury to the Company or its shareholders, (e) for acts or omissions
that constitute an unexcused pattern of inattention that amounts to an
abdication of the director's or officer's duty to the Company or its
shareholders, and (f) for liabilities arising under Section 310 (contracts in
which a director has a material financial interest) and Section 316 (certain
unlawful dividends, distributions, loans and guarantees) of the Law. In
addition, the Company may not indemnify directors and officers in circumstances
in which indemnification is expressly prohibited by Section 317 of the Law.

         The bylaws of the Company provide that the Company has the power to
indemnify directors and officers to the fullest extent permitted under
California law and the Company's Articles of Incorporation. The Company has
entered into indemnification agreements with its directors and officers which
require that the Company indemnify such directors and officers in all cases to
the fullest extent permitted by applicable provisions of the Law. The Company
also maintains a directors' and officers' liability insurance policy insuring
directors and officers of the Company for covered losses as defined in the
policy.

Item 7.  Exemption from Registration Claimed

         Not applicable.

Item 8.  Exhibits

       5.1  Opinion of Counsel of Southwest regarding legality of the securities
            to be registered
      23.1  Consent of Arthur Andersen LLP
      23.2  Consent of Counsel of Southwest (included in opinion filed as
            Exhibit 5.1 to this Registration Statement)
      24.1  Powers of Attorney
----------

                                      S-2
In lieu of the opinion of counsel or determination letter contemplated
by Item 601(b)(5) of Regulation S-K, Registrant hereby confirms that it has
submitted the Plan and undertakes that it will submit all amendments thereto to
the Internal Revenue Service (IRS) in a timely manner, and that it has made or
will make all changes required by the IRS in order to qualify the Plan under
Section 401 of the Internal Revenue Code.

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, unless the information required to be included
         in such post-effective amendment is contained in a periodic report
         filed by Registrant pursuant to Section 13 or Section 15(d) of the
         Securities Exchange Act of 1934 and incorporated herein by reference;

            (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 this Registration Statement, unless the information required to be
         included in such post-effective amendment is contained in a periodic
         report filed by Registrant pursuant to Section 13 or Section 15(d) of
         the Securities Exchange Act of 1934 and incorporated herein by
         reference;

           (iii) To include any material information with respect to the plan of
         distribution not previously disclosed in this Registration Statement or
         any material change to such information in this 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 further 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 each filing of the annual report of the
Plan 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 pursuant to the foregoing provisions, or otherwise, 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 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 Act and will be governed by the final adjudication of
such issue.

                                      S-3
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 Las Vegas, State of Nevada, on April 21, 2000.

                                     SOUTHWEST GAS CORPORATION

                              By        /s/ MICHAEL O. MAFFIE
                                -------------------------------------
                                          Michael O. Maffie
                                President and Chief Executive Officer

                                   SIGNATURES

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

     Signature                         Title                          Date
     ---------                         -----                          ----

 /s/ MICHAEL O. MAFFIE         Director, President and            April 21, 2000
-------------------------      Chief Executive Officer
    (Michael O. Maffie)     (Principal Executive Officer)

 /s/ GEORGE C. BIEHL        Director, Senior Vice President,      April 21, 2000
-------------------------     Chief Financial Officer and
    (George C. Biehl)             Corporate Secretary
                             (Principal Financial Officer)

 /s/ EDWARD A. JANOV        Vice President, Controller and        April 21, 2000
-------------------------      Chief Accounting Officer
    (Edward A. Janov)       (Principal Accounting Officer)

 /s/ MANUEL J. CORTEZ *               Director                    April 21, 2000
-------------------------
    (Manuel J. Cortez)

 /s/ LLOYD T. DYER *                  Director                    April 21, 2000
-------------------------
    (Lloyd T. Dyer)

 /s/ THOMAS Y. HARTLEY *         Chairman of the Board            April 21, 2000
-------------------------             of Directors
    (Thomas Y. Hartley)

 /s/ MICHAEL B. JAGER *               Director                    April 21, 2000
-------------------------
    (Michael B. Jager)

                                      S-4
Signature                         Title                          Date
     ---------                         -----                          ----

 /s/ LEONARD R. JUDD *                Director                    April 21, 2000
-------------------------
    (Leonard R. Judd)

 /s/ JAMES J. KROPID *                Director                    April 21, 2000
-------------------------
    (James J. Kropid)

 /s/ CAROLYN M. SPARKS *              Director                    April 21, 2000
-------------------------
    (Carolyn M. Sparks)

 /s/ ROBERT S. SUNDT *                Director                    April 21, 2000
-------------------------
    (Robert S. Sundt)

 /s/ TERRANCE L. WRIGHT *             Director                    April 21, 2000
-------------------------
    (Terrance L. Wright)

*  By      /s/ GEORGE C. BIEHL
      --------------------------
              (George C. Biehl)
               Attorney-in-fact

                                      S-5
The Plan

       Pursuant to the requirements of the Securities Act of 1933, the Southwest
Gas Corporation Employees' Investment Plan Committee has duly caused this
Registration Statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of Las Vegas, State of Nevada, on April 21, 2000.

                            SOUTHWEST GAS CORPORATION
                           EMPLOYEES' INVESTMENT PLAN
                                    COMMITTEE

                               /s/ GEORGE C. BIEHL
                            ------------------------
                                (George C. Biehl)

                                /s/ JAMES P. KANE
                            ------------------------
                                 (James P. Kane)

                                /s/ FRED W. COVER
                            ------------------------
                                 (Fred W. Cover)

                              /s/ THOMAS R. SHEETS
                            ------------------------
                               (Thomas R. Sheets)

                                      S-6
Exhibit Index

  Exhibit
  Number                              Description
 ---------         -----------------------------------------------------

    5.1            Opinion of Counsel of the Company regarding legality of the
                   securities to be registered

   23.1            Consent of Arthur Andersen LLP

   23.2            Consent of Counsel of the Company (included in opinion filed
                   as Exhibit 5.1 to this Registration Statement)

   24.1            Powers of Attorney