Abstract: Based on the room temperature creep analysis on propeller shaft under constant load condition, a dynamic analysis on the propeller shaft with deformation of 20-year creep is carried out. By choosing a proper creep model of ANSYS, and using finite element method ( ANSYS program) , a deflection line of propeller shaft at the time of 20-years is obtained. A modal analysis of the propeller shaft is done, and a comparison of natural frequency between a no-bending shaft and a shaft after creep is also made. Finally, calculations of the force on shaft and shaft response are carried out. After these analysis and calculations, it is concluded that the room temperature creep depresses the capability of the propeller shaft.