Abstract: Tensile tests were carried out by controlling consistent crosshead separation rate and the varieties of the strain rate of different strain-hardening materials were discussed. The issue that compliance of the testing machine should be considered at which time and on which type materials was detailedly and deeply analyzed. How to determine the compliance of the testing machine was demonstrated, and the strain rate on the sample could be controlled accurately by controlling consistent crosshead separation rate which was revised by the testing machine compliance when the compliance of the testing machine was considered.