The marked vehicle was responding to an emergency call on Glasgow's southside when the pedestrian was hit on Saturday evening.
Police Scotland said officers were en route to an incident on Ardmay Crescent near Aikenhead Road at about 11.35pm when the collision happened.
The man was taken to the Victoria Infirmary where he was last night detained for observation. His injuries are not thought to be life-threatening.
The road was temporarily closed as crash investigators examined the scene.