It happened on Monday at around 9 p.m. near West 110th Street and Lenox Avenue.
The 35-year-old victim told police she was with a female friend near the park walking when a male acquaintance of the friend showed up.
They were all talking together, and when the friend left, the victim told police the man offered to walk her home through the park.
While walking in Central Park, the man then took out a knife, assaulted and raped the woman.
He took off with her purse and cellphone, and ran off.
The suspect is described as approximately 30 years-old, 190lbs., with black hair and last seen wearing a black long-sleeve shirt, tan pants, brown shoes and carrying a black book bag.
Anyone with information is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782).