Abstract: The 316L stainless steel strainer screen of an automobile gearbox fractured in several places during its service. The fracture causes of the strainer screen were analyzed by means of macro analysis, fracture analysis, metallographic examination, composition analysis and micro analysis. The results show that the fracture mode of the 316L stainless steel strainer screen was fatigue fracture. During the drawing process, there were some defects on the surface of wire, such as delamination, scratch and hard inclusion particles near the surface. Work hardening occurred at the intersection of wire mesh during integrated mesh making. Under the joint action of the both sides, the strainer screen occurred fatigue fracture.