Abstract: Previous researches on the vibration performance of the double disk cantilever rotor (DDCR) haven't considered the flight mission's influence.But sometimes the performance of DDCR in flight is quite different from the ground test,especially for those fighter planes with great maneuver.In order to study the flight mission's influence,we set up the motion differential equations for two kinds of flight mission,horizontal hover and vertical dive hike.Rugger Kutta method is used to solve the equations.The initial conditions are all set zero.The effects of the flight mission on the vibration performance of DDCR are calculated and analyzed.In general,the flight mission will add centrifugal force and gyroscopic moment on the rotor,which will make the rotor vibrate transiently and will deflect the orbit of the axial center from the axis.The amplitude of the transient vibration is nearly 50% higher than that of stable state in this example.Meanwhile,the shaft will deform evidently.So,the influence of the flight mission on the rotor should not be neglected.