Abstract: In view of the situation of high scrap rate of hydraulic fixtures, and often appearing specimen skid or slip phenomenon which resulting in abnormal or even invalid test results during tensile test of high strength steels, the improvement scheme which changing specimen fixing mode and adding loading surface to the shoulder was proposed. The results show that after improvement of the hydraulic fixtures, not only the specimen skid or slip phenomenon during test was effectively avoided, but also some new applications were endued to the hydraulic fixtures of the tensile testing machine.