Peel Regional Police said emergency crews were called just after 11 p.m. to the area of Mississauga and Lakeshore roads.
Police said a car and motorcycle were involved in a collision and the motorcyclist was ejected.
The man driving the motorcyclist was taken to a trauma centre. No other injuries were reported.
Police said the driver of the car remained at the scene.
There is no word on what may have led to the crash.