Abstract: The mechanical properties of 304 austenitic stainless steel before and after strain strengthening were studied under stress control mode and strain control mode. The results show that stress control could accurately controlled the yield strength of materials after strain strengthening. Under strain control mode, the mechanical properties after strain strengthening were quite different. When using strain control mode to strengthen 304 austenitic stainless steel, the strain value could not exceed 10%. In practical application, stress could be regarded as the control value of strain strengthening and strain as the limiting value of strain strengthening.