Toronto police say the man was shot shortly before 1 a.m. ET on Tuesday morning, while sitting in a car parked behind an apartment complex at 44 Willowridge Rd.
The victim was rushed to hospital with life threatening injuries. Police say he died on Thursday.
Police have identified the victim as Kahivesa Kavenandjamo.
Investigators have asked for anyone with information to contact them at 416-808-7400, or to call Crime Stoppers at 416-222-8477.