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                                 CODE OF ETHICS
              FOR PRINCIPAL EXECUTIVE AND SENIOR FINANCIAL OFFICERS
                                       OF
                          MASSMUTUAL INSTITUIONAL FUNDS
                           MML SERIES INVESTMENT FUND

     This Code of Ethics (the "Code") for Principal Executive and Senior
Financial Officers has been adopted by those investment companies identified
above for which Massachusetts Mutual Life Insurance Company ("MassMutual") acts
as investment adviser (individually, a "Fund" and collectively, the "Funds"), to
effectuate compliance with Section 406 under the Sarbanes-Oxley Act of 2002 and
the rules adopted to implement Section 406. The Code applies to each Fund's
principal executive officer, principal financial officer, principal accounting
officer or controller, or persons performing similar functions ("Covered
Officers"). A listing of positions currently within the ambit of Covered
Officers for each Fund is attached as Exhibit A.(1)

1.   PURPOSES OF THE CODE

     This Code sets forth standards and procedures that are reasonably designed
to deter wrongdoing and to promote:

     -    honest and ethical conduct, including the ethical handling of actual
          or apparent conflicts of interest between personal and professional
          relationships;

     -    full, fair, accurate, timely, and understandable disclosure in reports
          and documents that the Funds file with, or submit to, the Securities
          and Exchange Commission ("SEC") and in other public communications
          made by the Funds;

     -    compliance with applicable governmental laws, rules and regulations;

     -    the prompt internal reporting of violations of this Code to an
          appropriate person identified in the Code; and

     -    accountability for adherence to this Code.

     It is acknowledged that, as a result of the contractual relationship
between each Fund and MassMutual, of which the Covered Officers are also
officers or employees, and subject to MassMutual's fiduciary duties to each
Fund, the Covered Officers will, in the normal course of their duties, be
involved in establishing policies and implementing decisions that may have
different effects on MassMutual and the Funds. It is further acknowledged that
the participation of the Covered Officers in such activities is inherent in the
contractual relationship between each Fund and MassMutual and is consistent with
the expectations of each Fund's Board of Trustees with respect to the
performance by the Covered Officers of their duties as officers of the Funds.

     In general, the principles that govern honest and ethical conduct,
including the avoidance of conflicts of interest between personal and
professional relationships, reflect, at the minimum, the

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(1) The obligations imposed by this Code on Covered Officers are separate from
and in addition to any obligations that may be imposed on such persons as
Covered Persons under the Code of Ethics adopted by the Funds dated August 4,
2003, under Rule 17j-1 of the Investment Company Act of 1940, as amended and any
other code of conduct applicable to Covered Officers in whatever capacity they
serve. This Code does not incorporate by reference any provisions of the Rule
17j-1 Code of Ethics and accordingly, any violations or waivers granted under
the Rule 17j-1 Code of Ethics will not be considered a violation or waiver under
this Code.

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following: (1) the duty at all times in performing any responsibilities as a
financial officer, controller, accountant or principal executive officer of a
Fund, to place the interests of the Fund ahead of personal interests; (2) the
fundamental standard that Covered Officers should not take inappropriate
advantage of their positions; (3) the duty to assure that each Fund's financial
statements and reports to shareholders are prepared honestly and accurately in
accordance with applicable rules, regulations and accounting standards; and (4)
the duty to conduct the Fund's business and affairs in an honest and ethical
manner. Each Covered Officer should be sensitive to situations that may give
rise to actual as well as apparent conflicts of interest.

2.   PROHIBITIONS

     The specific provisions and reporting requirements of this Code are
concerned primarily with promoting honest and ethical conduct and avoiding
conflicts of interest between personal and professional relationships.

     No Covered Officer may use information concerning the business and affairs
of a Fund (including the investment intentions of a Fund), or use his or her
ability to influence such investment intentions, for personal gain to himself or
herself, his or her family or friends or any other person or in a manner
detrimental to the interests of a Fund or its shareholders.

     No Covered Officer may use his or her personal influence or personal
relationships to influence the preparation and issuance of financial reports of
a Fund whereby the Covered Officer would benefit personally to the detriment of
the Fund and its shareholders.

     No Covered Officer shall, in connection with carrying out his or her
official duties and responsibilities on behalf of a Fund:

     (i)     employ any device, scheme or artifice to defraud a Fund or its
             shareholders;

     (ii)    intentionally cause a Fund to make any untrue statement of a
             material fact or omit to state a material fact necessary in order
             to make the statements made, in light of the circumstances under
             which they are made, not misleading in its official documents,
             regulatory filings, financial statements or communications to the
             public;

     (iii)   engage in any act, practice, or course of business which operates
             or would operate as a fraud or deceit upon any Fund or its
             shareholders;

     (iv)    engage in any manipulative practice with respect to any Fund;

     (v)     intentionally cause a Fund to fail to comply with applicable laws,
             rules and regulations, including failure to comply with the
             requirement of full, fair, accurate, understandable and timely
             disclosure in reports and documents that a Fund files with, or
             submits to, the SEC and in other public communications made by the
             Fund;

     (vi)    intentionally mislead or omit to provide material information to
             the Fund's independent auditors or to the Board of Trustees or the
             officers of the Fund or its investment adviser in connection with
             Fund related matters;

     (vii)   fail to notify the Code Administrator (as defined in Section 7
             below) promptly if he or she becomes aware of any existing or
             potential violations of this Code or applicable laws; or

     (viii)  retaliate against others for, or otherwise discourage, the
             reporting of actual or apparent violations of this Code.

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3.   REPORTS OF CONFLICTS OF INTERESTS

     If a Covered Officer becomes aware of an actual or apparent conflict of
interest under this Code, he or she must immediately report the matter to the
Code's Administrator. Upon receipt of such report, the Code Administrator will
take prompt steps to determine whether an actual conflict of interest exists or
appears to exist, and if so, will take steps (if possible) to resolve the
conflict or remedy the appearance thereof. If the Code Administrator determines
that no actual or apparent conflict exists, the Code Administrator shall meet
with the Covered Officer to advise him or her of such finding and of his or her
reason for taking no action. In lieu of determining whether a conflict or
appearance of conflict exists, the Code Administrator may in his or her
discretion refer the matter to the affected Fund's Board of Trustees or any
committee appointed by the Board to deal with such information.

     If the Code Administrator is involved or believed to be involved in the
conflict of interest or appearance of conflict of interest, the Covered Officer
shall report the matter directly to MassMutual's General Counsel, or his or her
designee, who shall take the same action as described above with respect to
resolving the matter.

4.   WAIVERS

     Any Covered Officer requesting a waiver of any provision of this Code must
submit a written request for such waiver to the Code Administrator, setting
forth the basis of such request and all necessary facts upon which such request
can be evaluated. The Code Administrator shall review such request and make a
written determination thereon.

     In determining whether to waive any of the provisions of this Code, the
Code Administrator shall consider whether the proposed action:

        (i)     is prohibited by this Code;

        (ii)    is consistent with honest and ethical conduct; and

        (iii)   will result in a conflict of interest between the Covered
                Officer's personal and professional obligations to a Fund.

     In lieu of determining whether to waive any provision of this Code, the
Code Administrator may in his or her discretion refer the matter to the affected
Fund's Board of Trustees or any committee appointed by the Board to deal with
such information.

5.   REPORTING REQUIREMENTS

     (a)  Each Covered Officer shall, upon becoming subject to this Code, be
presented with a copy of this Code by the Code Administrator, and shall affirm
in writing to the Code Administrator that he or she has received, read,
understands and shall adhere to this Code (See Exhibit B).

     (b)  At least annually, all Covered Officers shall be provided with a copy
of the current Code by the Code Administrator, and shall certify that they have
read and understand the Code and recognize that they are subject thereto (See
Exhibit B).

     (c)  At least annually, all Covered Officers shall certify that they have
complied with the requirements of this Code and that they have disclosed or
reported any violations of this Code to the Code Administrator (See Exhibit C).

     (d)  The Code Administrator shall submit a quarterly report to the Board
of Trustees or any committee appointed by the Board to deal with such
information, containing (i) a description of any report of a conflict of
interest or apparent conflict and the disposition thereof; (ii) a description of
any request for a waiver from this Code and the disposition thereof; (iii) any
violation of the Code that has been reported or found and the sanction imposed;
and (iv) any other significant information

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arising in connection with the Code, including any proposed amendments.

     (e)  Each Covered Officer shall notify the Code Administrator promptly if
he or she knows of or has a reasonable belief that any violation of this Code
has occurred or is likely to occur. Failure to do so is itself a violation of
this Code.

     (f) Any changes to or waivers of this Code, including "implicit" waivers
as defined in applicable SEC rules, will, to the extent required, be disclosed
by the Funds as provided by applicable SEC rules.(2)

6.   SANCTIONS

     Any violations of this Code shall be subject to the imposition of such
sanctions by MassMutual as may be deemed appropriate under the circumstances to
achieve the purpose of this Code and may include, without limitation, a letter
of censure, suspension from employment or termination of employment, in the sole
discretion of MassMutual, and/or removal as an officer of the Fund, in the sole
discretion of the Fund's Board of Trustees or any committee appointed by the
Board to deal with such information.

7.   ADMINISTRATION AND CONSTRUCTION

     (a)  The administration of this Code of Ethics shall be the responsibility
          of the Code Administrator of this Code, acting under the terms of this
          Code and the oversight of the Board of Trustees of the Fund or any
          committee appointed by the Board to deal with such information.

     (b)  The Code Administrator shall be the Compliance Officer of the Funds or
          his or her designee.

     (c)  The duties of such Code Administrator will include:

          (i)   maintaining a current list of the names of all Covered Officers;

          (ii)  furnishing all Covered Officers a copy of this Code and
                initially and periodically informing them of their duties and
                obligations thereunder;

          (iii) maintaining or supervising the maintenance of all records
                required by this Code, including records of waivers granted
                hereunder;

          (iv)  issuing interpretations of this Code which appear to the Code
                Administrator to be consistent with the objectives of this Code
                and any applicable laws or regulations;

          (v)   conducting such inspections or investigations as shall
                reasonably be required to detect and report any violations of
                this Code, with his or her recommendations to MassMutual's
                General Counsel, or his or her designee, and to the Board of
                Trustees of the affected Fund(s) or any committee appointed by
                them to deal with such information; and

          (vi)  periodically conducting educational training programs as needed
                to explain and reinforce the terms of this Code.

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(2) An "implicit waiver" is the failure to take action within a reasonable
period of time regarding a material departure from a provision of this Code that
has been made known to the Code Administrator, MassMutual's General Counsel, or
his or her designee, or an officer of the Trust.

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          (d)   In carrying out the duties and responsibilities described under
                this Code, the Code Administrator may consult with such other
                persons as the Code Administrator shall deem necessary or
                desirable, including legal counsel to the Trust, legal counsel
                to the Trustees who are not "interested persons," as that term
                is defined in the Investment Company Act of 1940, as amended
                (the "Disinterested Trustees"), and legal counsel to the Trust's
                investment adviser.

8.   REQUIRED RECORDS

     The Code Administrator shall maintain and cause to be maintained in an
easily accessible place the following records for the period required by
applicable SEC rules (currently six years following the end of the fiscal year
of the Fund in which the applicable event or report occurred):

          (a)   a copy of any Code which has been in effect during the period;

          (b)   a copy of each certification pursuant to the Code made by a
                Covered Officer during the period;

          (c)   a copy of each report made by the Code Administrator pursuant to
                this Code during the period;

          (d)   a list of all Covered Officers who are or have been required to
                make reports pursuant to this Code during the period, plus those
                person(s) who are or were responsible for reviewing these
                reports;

          (e)   a record of any request to waive any requirement of this Code,
                the decision thereon and the reasons supporting the decision;

          (f)   a record of any report of any conflict of interest or appearance
                of a conflict of interest received by the Code Administrator or
                discovered by the Code Administrator during the period, the
                decision thereon and the reasons supporting the decision; and

          (g)   a record of any violation of any such Code and of any action
                taken as a result of such violation, during the period.

9.   AMENDMENTS AND MODIFICATIONS

     This Code (other than Exhibit A and the names of the Funds identified on
the first page that have adopted the Code) may not be amended or modified except
by a writing that is approved or ratified by a majority vote of the Board of
Trustees and the Disinterested Trustees.

10.  CONFIDENTIALITY.

     This Code is for the internal use of the Funds. Reports and records
prepared or maintained under this Code are considered confidential and shall be
maintained and protected accordingly to the extent permitted by applicable laws,
rules and regulations. Except as otherwise required by law or this Code, such
matters shall not be disclosed to anyone other than the Trustees and their
counsel, Fund counsel, Fund officers, the independent auditors of the Funds, and
MassMutual or its counsel, except as such disclosure may be required pursuant to
applicable judicial or regulatory process.

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                                    EXHIBIT A

                    POSITIONS COVERED BY THIS CODE OF ETHICS

MASSMUTUAL INSTITUTIONAL FUNDS AND MML SERIES INVESTMENT FUND

Principal Executive Officer
Chief Financial Officer
Treasurer
Assistant Treasurer

PERSONNEL OF MASSMUTUAL WHO BY VIRTUE OF THEIR JOBS PERFORM CRITICAL FINANCIAL
AND ACCOUNTING FUNCTIONS FOR MASSMUTUAL ON BEHALF OF A FUND, INCLUDING:

Second Vice President/Fund Operations

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                                    EXHIBIT B

                          INITIAL/ANNUAL CERTIFICATION

By signing below I certify that I have received, read, and understand this Code
of Ethics for Principal Executive and Senior Financial Officers of the Funds
(the "Code"), and further certify that I shall adhere to this Code.


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Signature


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(Type or Print) Name and Title


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Date


Please return the executed certification to the Code Administrator.

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                                    EXHIBIT C

                    ANNUAL COMPLIANCE/REPORTING CERTIFICATION

By signing below, I certify that I have complied with the requirements of this
Code of Ethics for Principal Executive and Senior Financial Officers of the
Funds (the "Code"), and have disclosed or reported any violations of this Code
to the Code Administrator for the year ended 2003.


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Signature


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(Type or Print) Name and Title


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Date


Please return the executed certification to the Code Administrator.

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