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                                                                     EXHIBIT 3.1
 
                     RESTATED CERTIFICATE OF INCORPORATION
                       OF LYONDELL PETROCHEMICAL COMPANY
                           (A DELAWARE CORPORATION)

    (ORIGINALLY INCORPORATED ON NOVEMBER 15, 1985 AS LYONDELL PETROCHEMICAL
                                 CORPORATION)

 (AMENDED AND RESTATED AS OF MARCH 1, 1997 FOR ELECTRONIC SEC FILING PURPOSES
                                     ONLY)


                                   ARTICLE I
                                     NAME

          The name of the Company is LYONDELL PETROCHEMICAL COMPANY.


                                  ARTICLE II
                         ADDRESS AND REGISTERED AGENT

     The address of the Company's registered office in the State of Delaware is
Corporation Trust Center, 1209 Orange Street, Wilmington, County of New Castle,
Delaware, 19801.  The name of the registered agent at such address is The
Corporation Trust Company.


                                  ARTICLE III
                            DESCRIPTION OF BUSINESS

     The nature of the business or purposes to be conducted or promoted is to
engage in any lawful act or activity for which corporations may be organized
under the General Corporation Law of Delaware.


                                  ARTICLE IV
                                 CAPITAL STOCK

A.   AUTHORIZED SHARES

     The total number of shares of capital stock that the Company shall have
authority to issue is 330,000,000 shares.


B.   COMMON STOCK

     1.   The Company shall have authority to issue up to 250,000,000 shares of
Common Stock, par value of $1.00 per share.

     2.   Each holder of shares of Common Stock shall have the right to one vote
for each 
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share of Common Stock held of record on the books of the Company.


C.   PREFERRED STOCK

     1.   The Company shall have authority to issue up to 80,000,000 shares of
Preferred Stock, par value of $.01 per share.

     2.   Preferred Stock may be issued from time to time in one or more series.
The Board of Directors is hereby expressly authorized from time to time to
provide for the issuance of Preferred Stock in one or more series, and to
establish and fix by resolution or resolutions providing for the issuance of
each such series the number of shares to be included in such series and the
voting and other powers, designations, preferences and relative, participating,
optional or other special rights, and qualifications, limitations or
restrictions thereof, of each such series, to the full extent now or hereafter
permitted by law, subject to any other provision of this Certificate of
Incorporation.  The number of authorized shares of Preferred Stock may be
increased or decreased (but not below the number of shares thereof then
outstanding) by the affirmative vote of the holders of stock of the Company
entitled to vote thereon having a majority of the votes entitled to be cast,
without a separate vote of the holders of the Preferred Stock, or any series
thereof, unless a separate vote of any of such holders is required pursuant to
the resolution or resolutions establishing any such series of Preferred Stock.


                                   ARTICLE V
                  ANNUAL AND SPECIAL MEETINGS OF STOCKHOLDERS

     Any action required or permitted to be taken by the holders of the stock of
the Company may be effected either at a duly called annual or special meeting of
such holders or by consent in writing by such holders.  Except as otherwise
required by law, special meetings of stockholders of the Company may be called
only by the written consent of the stockholders owning a majority of the capital
stock issued and outstanding and entitled to vote or by the Board of Directors
pursuant to a resolution approved by a majority of the entire Board of Directors
or by the Chairman of the Board.


                                  ARTICLE VI
                                   DIRECTORS

     A.   The business and affairs of the Company shall be managed by the Board
of Directors, and the directors need not be elected by ballot unless required by
the By-Laws of the Company. The number of the directors of the Company shall be
fixed from time to time by, or in the manner provided in, the By-Laws of the
Company.

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     B.   Nominations for the election of directors may be made by the Board of
Directors or by any record owner of stock of the Company.

     C.   Newly created directorships resulting from any increase in the number
of directors or any vacancy on the Board of Directors resulting from death,
resignation, disqualification, removal or other cause may be filled by the
affirmative vote of a majority of the remaining directors then in office, even
though less than a quorum of the Board of Directors, by a sole remaining
director or by the affirmative vote of the majority of all votes entitled to be
cast by the holders of stock of the Company at a duly called annual or special
meeting of such holders or by consent in writing by such holders.  Any director
elected in accordance with the preceding sentence shall hold office until such
director's successor shall have been elected and qualified or until the
director's earlier resignation or removal.  No decrease in the number of
directors constituting the Board of Directors shall shorten the term of any
incumbent director.

     D.   Any one or more directors may be removed with or without cause, by the
holders of a majority of the shares then entitled to vote at an election of
directors.

     E.   The Board of Directors shall have the power to adopt, amend and repeal
the By-Laws of the Company.


                                  ARTICLE VII
                             DIRECTORS' LIABILITY

     To the fullest extent permitted by the General Corporation Law of Delaware
as the same exists or may hereafter be amended, a director of the Company shall
not be liable to the Company or its stockholders for monetary damages for breach
of fiduciary duty as a director.  If the General Corporation Law of Delaware is
amended to authorize corporate action further eliminating or limiting the
personal liability of directors, then the liability of a director of the Company
shall be eliminated or limited to the fullest extent permitted by the General
Corporation Law of Delaware, as so amended.  Any repeal or modification of this
Article VII by the stockholders of the Company shall not adversely affect any
right or protection of a director of the Company existing at the time of such
repeal or modification or with respect to events occurring prior to such time.
Notwithstanding anything contained in this Certificate to the contrary, the
affirmative vote of the holders of not less than 66-2/3 percent of all votes
entitled to be cast by the holders of stock of the Company shall be required to
amend or repeal this Article VII or to adopt any provision inconsistent
herewith.


                                 ARTICLE VIII
                    RELATIONS WITH SUBSTANTIAL STOCKHOLDER

     A.   In anticipation that (i) Atlantic Richfield Company, a Delaware
corporation, ("ARCO") will be and will remain a substantial stockholder of the
Company, (ii) the Company and 

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ARCO may engage in the same or similar activities or lines of business and have
an interest in the same areas of corporate opportunities, (iii) the Company and
ARCO may enter into contracts or otherwise transact business with each other and
that the Company may derive benefits therefrom and (iv) the Company may from
time to time enter into contractual, corporate or business relations with one or
more of its directors or one or more corporations, partnerships, associations or
other organizations in which one or more of its directors have a financial
interest (collectively, "Related Entities"), and in recognition of the benefits
to be derived by the Company through its continued contractual, corporate and
business relations with ARCO (including service of officers and directors of
ARCO as officers and directors of the Company), the provisions of this Article
VIII are set forth to regulate and define the conduct of certain affairs,
contractual relationships and other business relations of the Company as they
may involve ARCO, Related Entities and their respective officers and directors,
and the powers, rights, duties and liabilities of the Company and its officers,
directors and stockholders in connection therewith. The provisions of this
Article VIII are in addition to, and not in limitation of, the provisions of the
General Corporation Law of the State of Delaware and the other provisions of
this Restated Certificate of Incorporation. Any contract or business relation
which does not comply with the rules set forth in this Article VIII shall not by
reason thereof be deemed void or voidable or result in any breach of any
fiduciary duty, but shall be governed by the provisions of this Restated
Certificate of Incorporation, the By-Laws, the General Corporation Law of the
State of Delaware and by law.

     B.   ARCO shall have no duty to refrain from (i) engaging in the same or
similar activities or lines of business as the Company, (ii) doing business with
any customer of the Company, or (iii) employing or otherwise engaging any
officer or employee of the Company and neither ARCO nor any officer or director
thereof (except as provided in paragraph C below) shall be liable to the Company
or its stockholders for breach of any fiduciary duty by reason of any such
activities of ARCO or of such person's participation therein.  In the event that
ARCO acquires knowledge of a potential transaction or matter which may be a
corporate opportunity for both ARCO and the Company, ARCO shall have no duty to
communicate or offer such corporate opportunity to the Company and shall not be
liable to the Company or its stockholders for breach of any fiduciary duty as a
stockholder of the Company by reason of the fact that ARCO pursues or acquires
such corporate opportunity for itself, directs such corporate opportunity to
another person, or does not communicate information regarding such corporate
opportunity to the Company.

     C.   When a corporate opportunity is offered to an officer and/or director
of the Company who is an officer and/or director of ARCO in writing, solely in
his or her designated capacity with one of the two companies, such opportunity
shall be first presented to whichever company was so designated.  Otherwise, (i)
a corporate opportunity offered to any person who is an officer or officer and
director of the Company, and who is also a director (but not an officer) of ARCO
shall be first presented to the Company, (ii) a corporate opportunity offered to
a person who is a director (but not an officer) of the Company and who is also
an officer or an officer and director of ARCO shall be first presented to ARCO,
and (iii) in all other cases, a corporate opportunity offered to any person who
is an officer and/or director of the Company and who is also an officer and/or
director of ARCO shall be first presented to the Company.

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     D.   If any contract, agreement, arrangement or transaction between the
Company and ARCO involves a corporate opportunity and is approved in accordance
with the procedures set forth in paragraph E of this Article VIII, ARCO and its
officers and directors shall have fully satisfied and fulfilled their fiduciary
duties to the Company and its stockholders with respect thereto under this
Article VIII.  Any such contract, agreement, arrangement or transaction
involving a corporate opportunity not so approved shall not by reason thereof
result in any breach of any fiduciary duty, but shall be governed by the other
provisions of this Article VIII, this Restated Certificate of Incorporation, the
By-Laws, the General Corporation Law of the State of Delaware and by law.

     E.   No contract, agreement, arrangement or transaction between the Company
and ARCO or between the Company and one or more of the directors or officers of
the Company, ARCO or any Related Entity or between the Company and any Related
Entity shall be void or voidable for the reason that ARCO, any Related Entity or
one or more of the officers or directors of the Company, ARCO or any Related
Entities are parties thereto, or because any such directors or officers are
present at or participate in the meeting of the Board of Directors or committee
thereof which authorizes the contract, agreement, arrangement or transaction, or
because his, her or their votes are counted for such purpose, and ARCO, any
Related Entity and such directors and officers (a) shall have fully satisfied
and fulfilled their fiduciary duties to the Company and its stockholders with
respect thereto, (b) shall not be liable to the Company or its stockholders for
any breach of fiduciary duty by reason of any entering into, performance or
consummation of any such contract, agreement, arrangement or transaction, (c)
shall, in the case of officers and directors of the Company, be deemed to have
acted in good faith and in a manner such person reasonably believes to be in and
not opposed to the best interests of the Company and (d) shall, in the case of
officers and directors of the Company, be deemed not to have breached their
duties of loyalty to the Company and its stockholders and not to have derived an
improper personal benefit therefrom, if:

          (i)  The material facts as to the contract, agreement, arrangement or
transaction are disclosed or are known to the Board of Directors or the
committee thereof which authorizes the contract, agreement, arrangement or
transaction, and the Board of Directors or such committee in good faith
authorizes the contract, agreement, arrangement or transaction by the
affirmative vote of a majority of the disinterested directors, even though the
disinterested directors be less than a quorum; or

          (ii) The material facts as to the contract, agreement, arrangement or
transaction are disclosed or are known to the holders of capital stock entitled
to vote thereon, and the contract, agreement, arrangement or transaction is
specifically approved in good faith by vote of the holders of a majority of the
stock of the Company entitled to vote generally in the election of directors
voting together as a single class (other than any such stock owned by ARCO or a
Related Entity, as the case may be).

     F.   Contracts, agreements, arrangements or transactions entered into by
the Company or 

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any Related Entity with ARCO or any Related Entity that confer or execute equal
benefits on or to the parties are deemed to be arms length and the officers and
directors of the Company that approve and execute such contracts, agreements,
arrangements or transaction shall be deemed to have acted in good faith and in
and not opposed to the best interests of the Company.

     G.   Directors of the Company who are also directors or officers of ARCO or
any Related Entity may be counted in determining the presence of a quorum at a
meeting of the Board of Directors or of a committee which authorizes the
contract, agreement, arrangement or transaction.

     H.   Any person purchasing or otherwise acquiring any interest in shares of
the stock of the Company shall be deemed to have notice of and to have consented
to the provisions of this Article VIII.

     I.   For purposes of this Article VIII.

          1.   A director of the Company who is Chairman of the Board of
Directors of the Company or of a committee thereof shall not be deemed to be an
officer of the Company by reason of holding such position (without regard to
whether such position is deemed an office of the Company under the By-Laws of
the Company), unless such person is a full-time employee of the Company; and

          2.   "ARCO" shall include all successors to Atlantic Richfield Company
by way of merger, consolidation or sale of all or substantially all of its
assets, and all subsidiary corporations and all partnerships, joint ventures,
associations and other entities in which Atlantic Richfield Company owns
(directly or indirectly) fifty percent or more of the outstanding voting stock,
voting power, partnership interests or similar Ownership interests, but shall
not include the Company and its subsidiaries;

          3.   The "Company" shall include all subsidiary corporations and all
partnerships, joint ventures, associations and other entities in which the
Company owns (directly or indirectly) fifty percent or more of the outstanding
voting stock, voting power, partnership interests or similar ownership
interests; and any contract, agreement, arrangement or transaction with any such
entity, or with any officer or director thereof, shall be deemed to be a
contract, agreement, arrangement or transaction with the Company; and

          4.   "corporate opportunities" shall include, but not be limited to,
business opportunities which the Company is financially able to undertake, which
are, from their nature, in the line of the Company's business and are of
practical advantage to it, which are ones in which the Company has an interest
or a reasonable expectancy, and as to which by embracing the opportunity, the
self-interest of ARCO or the officer or director, as the case may be, will be
brought into conflict with that of the Company.

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     J.   Neither the alteration, amendment or repeal of this Article VIII, nor
the adoption of any provision inconsistent with this Article VIII, shall
eliminate or reduce the effect of this Article VIII in respect of any matter
occurring, or any cause of action, suit or claim that, but for this Article VIII
would accrue or arise, prior to such alteration, amendment, repeal or adoption.


                                  ARTICLE IX
                             OTHER CONSIDERATIONS

     The Board of Directors of the Company, when evaluating any offer of a
person, other than the Company itself, to (a) make a tender or exchange offer
for any equity security of the Company, (b) merge or consolidate the Company
with another person, or (c) purchase or otherwise acquire all or substantially
all of the properties and assets of the Company shall, in connection with the
exercise of its business judgment in determining what is in the best interests
of the Company and its stockholders, be entitled to give due consideration to
all factors that the Board of Directors determines to be relevant, including
without limitation the social and economic effects on the employees, customers,
suppliers and other constituents of the Company and its subsidiaries and on the
communities in which the Company and. its subsidiaries operate or are located.

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