Dec. 06, 2018
Emerging Markets Breakout Nations Portfolio
Emerging Markets Breakout Nations Portfolio
Summary Prospectus and Prospectus Supplement December 6, 2018 Morgan Stanley Institutional Fund, Inc. Supplement dated December 6, 2018 to the Morgan Stanley Institutional Fund, Inc. Summary Prospectus and Prospectus dated April 30, 2018 Emerging Markets Breakout Nations Portfolio (the "Fund")
Effective January 1, 2019, the Fund's primary benchmark index will change to MSCI Emerging Markets ex China Net Index. Also effective January 1, 2019, Tim Drinkall will no longer serve as a portfolio manager to the Fund. Accordingly, effective January 1, 2019, with respect to the Fund, all references to Mr. Drinkall will be removed from the Summary Prospectus and Prospectus.
Please retain this supplement for future reference.

If the Fund has annual returns for at least one calendar year, provide a table showing the Fund's (A) average annual total return; (B) average annual total return (after taxes on distributions); and (C) average annual total return (after taxes on distributions and redemption). A Money Market Fund should show only the returns described in clause (A) of the preceding sentence. All returns should be shown for 1-, 5-, and 10- calendar year periods ending on the date of the most recently completed calendar year (or for the life of the Fund, if shorter), but only for periods subsequent to the effective date of the Fund's registration statement. The table also should show the returns of an appropriate broad-based securities market index as defined in Instruction 5 to Item 22(b)(7) for the same periods. A Fund that has been in existence for more than 10 years also may include returns for the life of the Fund. A Money Market Fund may provide the Fund's 7-day yield ending on the date of the most recent calendar year or disclose a toll-free (or collect) telephone number that investors can use to obtain the Fund's current 7-day yield. For a Fund (other than a Money Market Fund or a Fund described in General Instruction C.3.(d)(iii)), provide the information in the following table with the specified captions AVERAGE ANNUAL TOTAL RETURNS (For the periods ended December 31, _____)

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph iii

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