Continuity mistake: The commandos are in the river, at night and they are setting the charges on the bridge, the variety show is going on at the same time. Between the British soldiers heads and the roof of the auditorium, the Japanese soldiers are standing in bright sunlight.
Other mistake: In the scene in the office with Jack Hawkins and William Holden, where William Holden is arm twisted into going back to the bridge, the oscillating fan, which is on and oscillating, has no blades, plus there is no breeze in the office. You can see the complete motor, plus the drive spindle, where the fan blade should be attached. It dominates the scene, along with the two actors.
Revealing mistake: The team going to mine the bridge waits until after dark. But as they move downstream you can see sunlight glinting off the water. Also in shots up towards the bridge you can see a lovely blue sky.
Factual error: In the headquarter scenes, the Jeep's windshield wipers had a distinctive aftermarket electric motor, which was not available until after the war.
Continuity mistake: In the very beginning of the movie a Japanese prisoner train is being filmed from the roof view with a Japanese soldier at a machine gun with a tripod riding on the roof. The Japanese soldier has his legs resting up on a wooden pallet type platform. When the train car approaches a few seconds later toward British soldiers a working on the train track the Japanese soldier's legs are now on the train car roof and no wooden pallet structure is visible. (01:01:01)
Other mistake: Near the end of the film, the demolition team plants the explosives at the base of the bridge supports, under the water. Yet, when Colonel Nicholson falls on the detonator, there are explosions on the bridge itself, far above where the charges were placed, regardless of the water level.