Three children had prolonged lipuria following femoral fracture. One case was further complicated by the bilateral development of urostealiths, rarely described fatty "calculi," with renal colic and hematuria. All patients are now asymptomatic. The observations in these three cases tend to support the concept that fat emboli are common following bone trauma. The emboli generally do not cause loss of renal function, and the diagnosis can be made by demonstration of lipids in the urine.