Perry, 65, was performing with "Hollywood Vampires" at the Ford Amphitheater on the Coney Island Boardwalk.
The band consists of Perry, Johnny Depp and Alice Cooper.
Video of the scene showed Perry playing the guitar before he suddenly walked toward a speaker and stumbled off-stage.
Perry was being evaluated in the emergency room, according to ABC affiliate WABC in New York City.
He was listed in stable condition at Coney Island Hospital, New York police confirmed to ABC News.
Perry was later transferred to Columbia Presbyterian Hospital for an unspecified reason, according to ABC News.