Abstract: The fracture of drive shaft was found in assembly line of a vehicle, which could not be restart after static testing.The fracture reason was analyzed by means of fracture analysis, metallographic examination, chemical composition analysis, hardness testing and so on.The results showed that the fracture belonged to brittle fracture, which caused by overburning under extortionate forging temperature.To ensure product quality and avoid overburning generated, it was advised to strengthen the control of forging temperature and holding time in the forging process of drive shaft.