The Los Angeles Police Department says officers responded to the 7600 block of Claybeck Avenue, near San Fernando Road, around 9:45 p.m. after a fight broke out between the suspect and the girl's father.
During the fight, the girl was somehow stabbed, LAPD said.
The suspect was seen handcuffed to a stretcher as he was being loaded into an ambulance.
The girl and her father, who were taken to an area hospital, are expected to be OK, officials say.