Document and Entity Information	0 Months Ended
Sep. 17, 2013
Risk/Return:
Document Type	497
Document Period End Date	Sep. 17, 2013
Registrant Name	MORGAN STANLEY INSTITUTIONAL FUND INC
Central Index Key	0000836487
Amendment Flag	false
Document Creation Date	Sep. 17, 2013
Document Effective Date	Sep. 17, 2013
Prospectus Date	Aug. 19, 2013
Global Quality Portfolio \| Class I
Risk/Return:
Trading Symbol	MGQIX
Global Quality Portfolio \| Class A
Risk/Return:
Trading Symbol	MGQAX
Global Quality Portfolio \| Class L
Risk/Return:
Trading Symbol	MGQLX

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The date the document was made available and submitted, in CCYY-MM-DD format. The date of submission, date of acceptance by the recipient, and the document effective date are all potentially different.

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The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word "Other".

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A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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The date of the prospectus.

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