Witnesses said warplanes on Friday dropped at least two bombs in the town's eastern neighbourhood of al-Askari, damaging 15 houses and destroying several cars.
Medical staff at the hospital in Falluja said four people were killed and 12 wounded, including a six-year-old girl.
US warplanes also bombed the city's industrial zone, wounding two factory guards.
The occupation military said at least one attack by its warplanes targeted an anti-aircraft gun being used by Iraqi fighters.
US warplanes bombarded Falluja for more than two hours on Wednesday, killing at least four people.
Falluja - west of the capital Baghdad - has been a hotbed of resistance against the occupation.