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                    [ANNOTATED FORM N-CSR FOR ANNUAL REPORTS]

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   FORM N-CSR

                   CERTIFIED SHAREHOLDER REPORT OF REGISTERED
                         MANAGEMENT INVESTMENT COMPANIES

Investment Company Act file
number: 811-05624
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Morgan Stanley Institutional Fund, Inc.
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               (Exact name of registrant as specified in charter)

1221 Avenue of the America's 22nd Floor New York, NY 10020
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      (Address of principal executive offices)                  (Zip code)

Ronald E. Robison
1221 Avenue of the Americas, 33rd Floor New York, New York 10020
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                     (Name and address of agent for service)

Registrant's telephone number, including area
code: 1-800-221-6726
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Date of fiscal year
end: 12/31
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Date of reporting
period: 12/31/04
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    Form N-CSR is to be used by management investment companies to file
reports with the Commission not later than 10 days after the transmission to
stockholders of any report that is required to be transmitted to stockholders
under Rule 30e-1 under the Investment Company Act of 1940 (17 CFR 270.30e-1).
The Commission may use the information provided on Form N-CSR in its
regulatory, disclosure review, inspection, and policymaking roles.

    A registrant is required to disclose the information specified by Form
N-CSR, and the Commission will make this information public. A registrant is
not required to respond to the collection of information contained in Form
N-CSR unless the Form displays a currently valid Office of Management and
Budget ("OMB") control number. Please direct comments concerning the accuracy
of the information collection burden estimate and any suggestions for reducing
the burden to Secretary, Securities and Exchange Commission, 450 Fifth Street,
NW, Washington, DC 20549-0609. The OMB has reviewed this collection of
information under the clearance requirements of 44 U.S.C. Section 3507.

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ITEMS 1-12.

The Fund's annual report transmitted to shareholders pursuant to Rule 30e-1
under the Investment Company Act of 1940 and filed under ITEM 1 of Form N-CSR
on March 9, 2005 and amended under ITEM 1 of Form N-CSR/A on April 22, 2005
is hereby incorporated by reference.

Responses to ITEMS 2-12 in the above mentioned filings, including related
attachments and exhibits are also hereby incorporated by reference, with the
exception of the certifications of the principal executive officer and
principal financial officer which are attached hereto as part of EX-99.CERT.

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                                   SIGNATURES

     Pursuant to the requirements of the Securities Exchange Act of 1934 and the
Investment Company Act of 1940, the registrant has duly caused this report to be
signed on its behalf by the undersigned, thereunto duly authorized.

(Registrant) Morgan Stanley Institutional Fund, Inc.
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By: /s/ Ronald E. Robison
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Name:    Ronald E. Robison
Title:   Principal Executive Officer
Date:    6/22/2005

     Pursuant to the requirements of the Securities Exchange Act of 1934 and the
Investment Company Act of 1940, this report has been signed by the following
persons on behalf of the registrant and in the capacities and on the dates
indicated.

By: /s/ Ronald E. Robison
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Name:    Ronald E. Robison
Title:   Principal Executive Officer
Date:    6/22/2005

By: /s/ James W. Garrett
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Name:    James W. Garrett
Title:   Chief Financial Officer
Date:    6/22/2005