WATCH: Video shows Aussie attacked in New York
After he ran off, she walked almost 2.5km to the NYPD's 90th Precinct on Union Avenue, where she told police what happened.
The woman, who has been in the US for about four months, was taken by ambulance to Woodhull Medical Center, where she was listed in stable condition.
Police released a video of the woman being attacked and asked the public for help to capture the man.
Police say he is a black male in the 20s who is about 6 feet tall.
They are also now offering a $US2500 ($A3500) reward for information leading to an arrest.
Residents in the East Williamsburg area say they are shaken up by the attack.