The incident happened on Thursday, just after midnight on East 150th Street and Wales Avenue in the Melrose section.
Police say the man attempted to rape a 20-year-old woman.
He eventually ran off northbound on Wales Avenue.
The woman was not hurt.
The suspect is described as a man wearing a black hat, red t-shirt, blue jeans, and white sneakers.
Anyone with information regarding this incident is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782).
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