Saskatoon police say they were notified of the collision around 9:30 a.m. Tuesday.
The crane was being hauled on the back of a vehicle when it hit the pedestrian overpass.
A statement from the City of Saskatoon said the collision caused damage and knocked the structure out of alignment.
A bridge inspection and structural assessment is underway and the bridge will remain closed until further notice.
The city statement added detours are in place and one westbound lane of traffic will be rerouted into an eastbound lane between Campus Drive and Cumberland Avenue.
Drivers are asked to avoid the area until structural damage can be assessed.
Police will provide an update when one is available.