Based on the theory of reliability analysis, the reliability of the crankshaft of high-speed punch was analyzed using the probability design functions of finite element analysis software (ANSYS-PDS module). The analysis file was written using parameter-design language APDL, and the geometry size, the load and the elastic modulus of the crankshaft were chosen as the random input variables. The reliability of the crankshaft, the response sensitivity and the main factors that affect the reliability were got, which were random sampling calculated by the central composite design sampling(CCD sampling) method of the response-surface method. The results show that the crankshaft yield limit and shaft neck size of crankshaft reliability influence is bigger. Thus the influence of the crankshaft reliability design variables and the target variables were got, which provides reference for improving the reliability of the crankshaft and the structure reliability optimization design.