He was outside the Mobil in the 7500-block of North Sheridan Road in the city's Rogers Park neighborhood around 2:40 a.m., when police said another male approached him and opened fire.
Bullet casings show the incident started near the gas station, then victim was chased down Howard where he was fatally shot. The teen suffered gunshot wounds to the head and abdomen, at close range.
The victim was taken to Saint Francis Hospital in Evanston, where he was pronounced dead. His identity has not yet been released.
There are surveillance cameras near the scene, which should help Area North detectives in their investigation.
No one is in custody.