[en] The carbon fiber composite cylindrical shell are composed of spiral winding layer and hoop winding layer, for researching the spiral winding layer stiffness degradation rule of the carbon fiber cylindrical composite shell with rotating load, based on the thin-shell theory, the analytical expressions for the model frequency of the cylinder are derived by creating the differential equations for the shell and then per 50 s^-1 velocity increased test is designed to getting frequency change rule after test by experimented, at last the results of spiral winding layer stiffness degradation rule is obtained by theoretically analysis agrees with the frequency change rule, and the others material parameters have no change. We should take stiffness degradation into account when designing the carbon fiber cylindrical composite shell with rotating load. (authors)