Police say the shooting happened just before 9:30 p.m. near Beacon Avenue South and South Columbian Way.
An officer at the scene said a man was working on his car with his teenage son and a man in his early 20s when a white Acura drove by and fired at least six shots.
The teenager and the man in his 20s both suffered multiple gunshot wounds to the upper legs. Both were taken to Harborview Medical Center with serious but not life-threatening injuries. The father was not injured.
A witness at the scene said the father was armed with a handgun and shot back at the car as it drove away.
It's unclear what led up to the shooting or if police have made any arrests in the case.