Acting Essex County Prosecutor Carolyn Murray says the teen was grazed in the shoulder.
The teen has been charged with assaulting a police officer.
The shooting occurred at about 12:35 a.m. Friday. Irvington police responded to a call about youths damaging a vehicle and soon spotted the 15-year-old and a 16-year-old boy who fit the caller's description.
The older teen ran off but was soon caught. He hasn't been charged.
The other youth ran into the apartment hallway. Authorities say the officer feared for his life and drew his service weapon.
The shooting will be reviewed by the prosecutor's office.
Names of those involved were not released.