Officials said the incident occurred 26 November as the lawmakers were traveling to the Baghdad airport.
Officials said the two members of the House of Representatives -- Ike Skelton (Democrat, Missouri) and Tim Murphy (Republican, Pennsylvania) -- received their injuries when the military vehicle they were traveling in went off the road and overturned, apparently while trying to avoid an on-coming vehicle.
Officials said there was no evidence that the lawmakers had come under intentional attack.
The injuries to the two congressmen were described as non-serious, but they were later flown to a U.S. military medical center in Germany for tests.
A third U.S. lawmaker who was also in the vehicle was not hurt.