A woman fought off an attempted rapist who groped her inside her Harlem apartment building, police said Sunday.

The suspect followed the 22-year-old woman into the vestibule of her building near East 128th Street and 5th Avenue at about 4:45 a.m. on Saturday, authorities said.

The man then grabbed the woman’s rear end, but she fought back, video of the attempted assault shows.

As the two struggled, the suspect grabbed the woman’s throat in an attempt to subdue her, police said.

The suspect eventually gave up and ran out of the building. He was last seen heading east on 128th Street near Madison Avenue, authorities said.

He’s described as a man in his mid-30s who is about 6-foot-1, police said.