Through high temperature superplastic tensile test, analysis of tensile axial force and temperature control error of the high temperature superplastic tensile test equipment was done to find the errors effect of tensile axial force and the thermostat on the tensile test results, and to offer ways for correcting tensile test equipment and temperature control system. Using high temperature superplastic tensile method with the maximun value of m, TB6 material sample was used to do high temperature superplastic tensile test, dispose and analyze the test data, and then the experimental data error of the high temperature superplastic tensile test which was led by the tensile axial force and temperature control error was corrected.