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                                                                     EXHIBIT 3.1

                     RESTATED CERTIFICATE OF INCORPORATION

                                      OF

                             THE WISER OIL COMPANY

     The Wiser Oil Company, a corporation organized and existing under the laws
of the State of Delaware (the "Corporation"), hereby certifies as follows:

     1.   The present name of the Corporation is The Wiser Oil Company.  The
Corporation was originally incorporated under the name Petex-Wiser Corporation,
the original Certificate of Incorporation having been filed with the Secretary
of State of Delaware on September 16, 1970.

     2.   The within Restated Certificate of Incorporation restates and
integrates and also further amends the provisions of the Corporation's
Certificate of Incorporation as heretofore amended or supplemented.  The within
Restated Certificate of Incorporation was duly adopted in accordance with the
provisions of Section 242 and Section 245 of the General Corporation Law of the
State of Delaware.

     3.   The text of the Corporation's Certificate of Incorporation as
heretofore amended or supplemented is hereby restated and further amended to
read in its entirety as follows:

     First: The name of the Corporation is The Wiser Oil Company.

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

     Third: The nature of the business and purposes to be conducted and promoted
by the Corporation is to conduct any lawful business, to promote any lawful
purpose and to engage in any lawful act or activity for which corporations may
be organized under the General Corporation Law of Delaware.

     Fourth: The aggregate number of shares of all classes of capital stock
which the Corporation shall have authority to issue is 31,300,000 shares, of
which 30,000,000 shares shall be Common Stock of the par value of $.01 per share
and 1,300,000 shares shall be Preferred Stock of the par value of $10 per share.
Upon the filing of this Restated Certificate of Incorporation with the Secretary
of State of Delaware, each outstanding and treasury share of Common Stock, par
value $3 per share, of the Corporation is hereby immediately and automatically
reclassified as and converted into one outstanding or treasury share of new
Common Stock of the par value of $.01 per share.  Each person who, at the time
of such filing, is the holder of a certificate or certificates evidencing shares
of the then outstanding Common Stock of the Corporation will thereafter be
entitled, upon surrendering such person's certificates to the Corporation at its
principal place of business, to receive in exchange therefor one or more
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certificates representing the number of shares of the new Common Stock of the
Corporation into which such person's aggregate number of shares of Common Stock
will have been so reclassified and converted.

     The Preferred Stock may be issued from time to time in one or more series.
Each series of Preferred Stock shall be distinctively designated by letter or
descriptive words.  All series of Preferred Stock shall rank equally and be
identical in all respects except as set forth in the resolutions of the Board of
Directors of the Corporation providing for the issue of such stock.

     Authority is hereby expressly vested in the Board of Directors from time to
time to issue the Preferred Stock as Preferred Stock of any series, and in
connection with the creation of each such series to fix by resolution or
resolutions providing for the issue of shares thereof the voting powers, if any,
the designation, the preferences and relative, participating, optional or other
special rights, and the qualifications, limitations or restrictions, of such
series to the full extent now or hereafter permitted by the laws of the State of
Delaware.

     Fifth: The following provisions are inserted for the management of the
business and for the conduct of the affairs of the Corporation and for the
purpose of creating, defining, limiting and regulating the powers of the
Corporation and its directors and stockholders:

          (a)  Elections of directors need not be by written ballot unless the
     Bylaws of the Corporation shall so provide.

          (b)  The Corporation reserves the right to amend, alter, change or
     repeal any provision contained in this Restated Certificate of
     Incorporation, and to merge, sell its assets and take other corporate
     action, to the extent and in the manner now or hereafter permitted or
     prescribed by statute, and all rights conferred upon stockholders herein
     are granted subject to this reservation.

     Sixth: Whenever a compromise or arrangement is proposed between this
Corporation and its creditors or any class of them and/or between this
Corporation and its stockholders or any class of them, any court of equitable
jurisdiction within the State of Delaware may, on the application in a summary
way of this Corporation or of any creditor or stockholder thereof or on the
application of any receiver or receivers appointed for this Corporation under
the provisions of section 291 of Title 8 of the Delaware Code or on the
application of trustees in dissolution or of any receiver or receivers appointed
for this Corporation under the provisions of section 279 of Title 8 of the
Delaware Code order a meeting of the creditors or class of creditors, and/or of
the stockholders or class of stockholders of this Corporation, as the case may
be, to be summoned in such manner as the said court directs.  If a majority in
number representing three-fourths in value of the creditors or class of
creditors, and/or of the stockholders or class of stockholders of this
Corporation, as the case may be, agree to any compromise or arrangement and to
any reorgani  zation of this Corporation as consequence of such compromise or
arrangement, the said compromise or arrangement and the said reorganization
shall, if sanctioned by the court to which the said application has been made,
be binding on all the creditors or class of creditors, and/or on

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all the stockholders or class of stockholders, of this Corporation, as the case
may be, and also on this Corporation.

     Seventh:

     Section 7.1.   Management of Business and Affairs.  The business and
affairs of the Corporation shall be managed by or under the direction of a Board
of Directors.

     Section 7.2.   Composition of Board.  The Board of Directors shall be
comprised as follows:

          (a)  Number. The whole Board of Directors shall consist of such number
     of persons, not less than 3 nor more than 14, as may from time to time be
     determined by the Board pursuant to a resolution adopted by a two-thirds
     vote of all the directors in office.

          (b)  Classification; Term of Office. Beginning with the Board of
     Directors to be elected at the annual meeting of stockholders to be held in
     1985, the directors shall be classified, in respect to the time for which
     they shall severally hold office, by dividing them into three classes, each
     such class to be as nearly equal in number as possible. At the annual
     meeting of stockholders to be held in 1985, separate elections shall be
     held for the directors of each class, the term of office of directors of
     the first class to expire at the first annual meeting after their election;
     the term of office of the directors of the second class to expire at the
     second annual meeting after their election; and the term of office of the
     directors of the third class to expire at the third annual meeting after
     their election. At each succeeding annual meeting, the stockholders shall
     elect directors of the class whose term then expires, to hold office until
     the third succeeding annual meeting. Each director shall hold office for
     the term for which elected and until his or her successor is elected and
     qualified or until his or her earlier resignation or removal.

          (c)  Removal of Directors. Stockholders may remove a director or the
     entire Board of Directors from office at any time only for cause and only
     by vote of two-thirds of the Voting Power of the outstanding shares of
     Voting Stock of the Corporation, voting together as a single class. The
     term "Voting Stock" at any time shall mean the outstanding shares of
     capital stock of the Corporation entitled to vote at its next annual
     election of directors (without consideration of the rights of any class of
     stock other than the Common Stock to elect directors by a separate class
     vote); and a specified percentage of "Voting Power", with reference to any
     matter being voted upon by the stockholders, shall mean such number of
     shares of stock as shall enable the holders thereof to cast such percentage
     of the total number of votes entitled to be cast by holders of shares
     entitled to vote thereon.

          (d)  Vacancies. Vacancies in the Board of Directors, including newly
     created directorships resulting from an increase in the number of
     directors, shall be filled only by a two-thirds vote of all the directors
     in office. All directors elected to fill vacancies shall hold office for a
     term expiring at the annual meeting of stockholders at which the term of
     the class to which they have been elected expires. No decrease in the
     number of directors constituting the Board of Directors shall shorten the
     term of an incumbent director.

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          (e)  Preferred Stock Directors. If at any time the holders of any
     class or series of Preferred Stock shall have the right, voting separately
     as a class, to elect one or more directors of the Corporation, none of the
     foregoing provisions of this Section 7.2 shall apply with respect to the
     director or directors elected by such holders of Preferred Stock.

     Eighth:

     Section 8.1.   Bylaws. The Board of Directors shall have the power to
adopt, amend or repeal Bylaws of the Corporation, except to the extent that
Bylaws adopted by the stockholders may otherwise provide. No Bylaws may be
adopted, amended or repealed by the stockholders unless such action is approved
by the vote of two-thirds of the Voting Power of the outstanding shares of
Voting Stock of the Corporation, voting together as a single class.

     Section 8.2.   Amendments to Restated Certificate of Incorporation. Subject
to the voting rights given to any particular class or series of Preferred Stock
by the Board of Directors pursuant to Article Fourth of this Restated
Certificate of Incorporation, and except as may be specifically provided to the
contrary in any other provision in this Restated Certificate of Incorporation
with respect to amendment or repeal of such provision, the vote of two-thirds of
the Voting Power of the outstanding shares of Voting Stock of the Corporation,
voting together as a single class, shall be required to amend the provisions of
Articles Seventh and Eighth of this Restated Certificate of Incorporation or
delete any provision of such Articles.

     Section 8.3.   Stockholder Meetings. Subject to the rights of the holders
of any class or series of Preferred Stock to take action separately as a class,
any action required or permitted to be taken by the stockholders of the
Corporation must be effected at a duly called annual or special meeting of such
stockholders and may not be effected without a meeting by any consent in writing
by such stockholders. Except as otherwise required by law and subject to the
rights of the holders of any class or series of Preferred Stock, special
meetings of stockholders of the Corporation may be called only by the Chairman
of the Board, the President or the Board of Directors.

     Ninth: To the fullest extent permitted by the General Corporation Law of
the State of Delaware as the same now exists or may hereafter be amended, a
director of the Corporation shall not be personally liable to the Corporation or
its stockholders for monetary damages for breach of fiduciary duty as a
director.

     Tenth:

     Section 10.1.  Indemnification of Directors and Officers.  Except as
prohibited by law, every director and officer of the Corporation shall be
entitled as a matter of right to be indemnified by the Corporation against all
expenses and liability (as those terms are defined below in this Section 10.1)
incurred by such person in connection with any actual or threatened claim,
action, suit or proceeding, civil, criminal, administrative, investigative or
other, whether brought by or in the right of the Corporation or otherwise, in
which such person may be involved, as a party or otherwise, by reason of such
person being or having been a director or officer of the Corporation or of a
subsidiary of the Corporation or by reason of the fact that such person is or
was serving at the request of the Corporation as a director, officer, employee,

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fiduciary or other representative of another corporation, partnership, joint
venture, trust, employee benefit plan or other entity (such claim, action, suit
or proceeding hereinafter being referred to as "Action"); provided, however,
that no such right to indemnification shall exist with respect to an Action
brought by an indemnitee (as defined below) against the Corporation (an
"Indemnitee Action") except as provided in the last sentence of this Section
10.1. Persons who are not directors or officers of the Corporation may be
similarly indemnified in respect of service to the Corporation or to another
such entity at the request of the Corporation to the extent the Board of
Directors of the Corporation at any time designates any of such persons as
entitled to the benefits of this Article Tenth. As used in this Article Tenth,
"indemnitee" shall include each director and officer of the Corporation and each
other person designated by the Board of Directors of the Corporation as entitled
to the benefits of this Section 10.1; "expenses" means all expenses actually and
reasonably incurred, including fees and expenses of counsel selected by an
indemnitee, and "liability" means all liability incurred, including the amounts
of any judgments, excise taxes, fines or penalties and any amounts paid in
settlement. An indemnitee shall be entitled to be indemnified pursuant to this
Section 10.1 against expenses incurred in connection with an Indemnitee Action
only if (i) the Indemnitee Action is instituted under Section 10.3 of this
Article Tenth and the indemnitee is successful in whole or in part in such
Indemnitee Action, (ii) the indemnitee is successful in whole or in part in
another Indemnitee Action for which expenses are claimed or (iii) the
indemnification for expenses is included in the settlement of, or is awarded by
a court in, such other Indemnitee Action.

     Section 10.2.  Right to Advancement of Expenses.  Every indemnitee shall be
entitled as a matter of right to have the expenses of the indemnitee in
defending any Action or in bringing and pursuing any Indemnitee Action under
Section 10.3 of this Article Tenth paid in advance by the Corporation prior to
final disposition of the Action or Indemnitee Action provided that the
Corporation receives a written undertaking by or on behalf of the indemnitee to
repay the amount advanced if it should ultimately be determined that the
indemnitee is not entitled to be indemnified for the expenses.

     Section 10.3.  Right of Indemnitee to Bring Action.  If a written claim for
indemnification under Section 10.1 of this Article Tenth or for advancement of
expenses under Section 10.2 of this Article Tenth is not paid in full by the
Corporation within 30 days after the claim has been received by the Corporation,
the indemnitee may at any time thereafter bring an Indemnitee Action to recover
the unpaid amount of the claim and, if successful in whole or in part, the
indemnitee shall also be entitled to be paid the expense of bringing and
pursuing such Indemnitee Action.  The only defense to an Indemnitee Action to
recover on a claim for indemnification under Section 10.1 of this Article Tenth
shall be that the conduct of the indemnitee was such that under Delaware law the
Corporation is prohibited from indemnifying the indemnitee for the amount
claimed, but the burden of proving such defense shall be on the Corporation.
Neither the failure of the Corporation (including its Board of Directors,
independent legal counsel and stockholders) to have made a determination prior
to the commencement of such Indemnitee Action that indemnification of the
indemnitee is proper in the circumstances, nor an actual determination by the
Corporation (including its Board of Directors, independent legal counsel or
stockholders) that the conduct of the indemnitee was such that indemnification
is prohibited by Delaware law, shall be a defense to such Indemnitee Action or
create a presumption that the conduct of the indemnitee was such that
indemnification is prohibited by Delaware law.  The only defense to an
Indemnitee Action to recover on a claim for advancement of expenses under

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Section 10.2 of this Article Tenth shall be failure by the indemnitee to provide
the undertaking required by Section 10.2 of this Article Tenth.

     Section 10.4.  Funding and Insurance.  The Corporation may create a trust
fund, grant a security interest, cause a letter of credit to be issued or use
other means (whether or not similar to the foregoing) to ensure the payment of
all sums required to be paid by the Corporation to effect indemnification as
provided in this Article Tenth.  The Corporation may purchase and maintain
insurance to protect itself and any indemnitee against any expenses or liability
incurred by the indemnitee in connection with any Action, whether or not the
Corporation would have the power to indemnify the indemnitee against the
expenses or liability by law or under the provisions of this Article Tenth.

     Section 10.5.  Non-Exclusivity; Nature and Extent of Rights.  The rights to
indemnification and advancement of expenses provided for in this Article Tenth
shall (i) not be deemed exclusive of any other rights, whether now existing or
hereafter created, to which any indemnitee may be entitled under any agreement,
provision in the Restated Certificate of Incorporation or Bylaws of the
Corporation, vote of stockholders or disinterested directors or otherwise, (ii)
be deemed to create contractual rights in favor of each indemnitee who serves
the Corporation at any time while this Section 10.5 is in effect (and each such
indemnitee shall be deemed to be so serving in reliance on the provisions of
this Section 10.5), (iii) continue as to each indemnitee who has ceased to have
the status pursuant to which the indemnitee was entitled or was denominated as
entitled to indemnification under this Article Tenth and shall inure to the
benefit of the heirs and legal representatives of each indemnitee and (iv) be
applicable to Actions commenced after this Article Tenth becomes effective,
whether arising from acts or omissions occurring before or after this Article
Tenth becomes effective.  Any amendment or repeal of this Article Tenth or
adoption of any Bylaw of the Corporation or other provision of the Restated
Certificate of Incorporation of the Corporation which has the effect of limiting
in any way the rights to indemnification or advancement of expenses provided for
in this Article Tenth shall operate prospectively only and shall not affect any
action taken, or any failure to act, by an indemnitee prior to such amendment,
repeal, Bylaw or other provision becoming effective.

     Section 10.6.  Partial Indemnity.  If an indemnitee is entitled under any
provision of this Article Tenth to indemnification by the Corporation for some
or a portion of the expenses or liabilities incurred by the indemnitee in the
preparation, investigation, defense, appeal or settlement of any Action or
Indemnitee Action but not, however, for the total amount thereof, the
Corporation shall indemnify the indemnitee for the portion of such expenses or
liabilities to which the indemnitee is entitled.

     ELEVENTH: This Restated Certificate of Incorporation integrates without
further amendment hereby and shall be deemed to include the Certificate of
Designation, Preferences and Rights of Series B Preferred Stock of The Wiser Oil
Company filed with the Secretary of State of Delaware on November 12, 1993.

     IN WITNESS WHEREOF, the Corporation has caused this Restated Certificate of
Incorporation to be signed this 25th day of May, 2000.

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                             THE WISER OIL COMPANY


                             By:  /s/ Andrew J. Shoup, Jr.
                                ------------------------------
                                Name:   Andrew J. Shoup, Jr.
                                     -------------------------
                                Title:  President
                                      ------------------------

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