Tamir Phillips, of the 3000 block of Knights Road in Bensalem, was taken into custody at the Burlington County Prosecutor's Office on Monday night and is being held at the county jail.
The shooting happened around 3 p.m. Saturday at the Phillips 66 gas station on the unit block of Martin Luther King Jr. Blvd. in Willingboro Township.
Police say the shooting appears to have been related to a stolen vehicle report from a day before.
According to investigators, the driver of a 2014 Honda Civic had contacted police to report the vehicle stolen on Friday.
The owner would frequently allow Phillips to use the car, police said.
On Saturday afternoon, police say Phillips was riding in a vehicle being driven by his girlfriend when they spotted the stolen Civic at the gas station pumps.
Police say Phillips' girlfriend pulled up behind the Civic, which was being driven by 14-year-old Jesse Everett.
Phillips went to the driver's side of the Civic, police say. There was a confrontation, and Phillips allegedly fired a single shot into the vehicle, striking Everett in the head.
He was pronounced dead later that afternoon at the hospital. Two other people were inside the Civic but were not injured.
Phillips and his girlfriend, identified as 29-year-old Chelsea Holman of Willingboro, then drove away after the shooting.
Holman has been charged with hindering apprehension and obstruction of justice. Police say she was not detained.