Abstract: The gas turbine output shaft is different from the power output shaft that is used at the diesel engine; its structure designs different, and needs to bear large external load. In order to raise the credibility and maintenance of gas turbine, by using the simplification theory and finite element software ANSYS, its strength and stiffness are calculated. It is concluded that the structural design of this shaft meets the needs of gas turbine operation, and its modeling and calculation analysis methods provide theoretical basis and design analysis methods for the next step of using gas turbines in tracked vehicles in China.