Abstract: Clinching tests were carried out after AZ31 magnesium alloy sheets in thickness of 1 mm were heated by female die heating at temperature range of 150-375 ℃. The joint strength was tested using shear test and tensile test. The results show that the suitable range of die temperature was 250 ℃ to 350 ℃. If the temperature was too low, fracture in the neck would happen. If the temperature was too high, hole punching in the bottom of joints would be found. And the best die temperature was around 300 ℃ at which the joint strength was the highest. The normal bearing force of the joint clinched at 300 ℃ was 600 N and the shear bearing force was 1 600 N.