Traumatic bilateral renal artery thrombosis is a rare injury that may be under-diagnosed. The clinical hallmarks include epigastric or flank pain and proteinuria, or hematuria following blunt trauma to the back or abdomen. Traditional practice suggests that revascularization should not be attempted more than 20 hours after injury. A patient is described in whom the retroperitoneum was explored 48 hours after injury and was found to have bilateral renal artery thrombosis. Although no repair was attempted, renal function spontaneously improved over several weeks. The clinical course of this patient suggests that revascularization should be considered even if the diagnosis is made more than 20 hours after injury.