Police say he pulled a knife to defend himself, and stabbed 15-year-old Keyanna Jones in the chest.
She was pronounced dead at Jamaica Hospital.
Following the stabbing, the group grabbed the man and held him for police.
The man was taken to the 113rd Precinct, where he told detectives the stabbing was in self defense.
He sustained injuries consistent to a beating, leading investigators to believe his story.
Charges are likely manslaughter and criminal possession of a weapon, and are pending consultation with the Queens District Attorney's Office.
