Document and Entity Information	Jul. 26, 2017
Prospectus:
Document Type	497
Document Period End Date	Jul. 26, 2017
Registrant Name	MORGAN STANLEY US GOVERNMENT MONEY MARKET TRUST
Central Index Key	0000356409
Amendment Flag	false
Document Creation Date	Jul. 26, 2017
Document Effective Date	Jul. 26, 2017
Prospectus Date	May 31, 2017
MORGAN STANLEY US GOVERNMENT MONEY MARKET TRUST \| R Class
Prospectus:
Trading Symbol	DWGXX
MORGAN STANLEY US GOVERNMENT MONEY MARKET TRUST \| S Class
Prospectus:
Trading Symbol	DGEXX

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