The incident happened Saturday night at Graham Street and Hillgate Lane. Police say the driver did not know the street ended and drove into the canal.
The water level came all the way up to the car's windows, which prevented him from opening the doors.
A diver went in and was able to pull the man out. Firefighters then used a ladder to hoist him to safety.
The man was taken to the hospital, but details on his condition were not available.