This paper takes the safety monitoring in the process of vibration test of aero-engine rake as the demand traction. Firstly， based on the simplified model of rake structure characteristics， the vibration characteristic equation of cracked rake is established. Secondly， a finite element model of rake is established， and the influence of crack parameters （such as position， crack length） on the natural frequency of the rake is analyzed by numerical simulation. Finally， the vibration test of this type of rake is carried out. The results of the frequency sweep test verify the accuracy of the finite element model of the rake. During the vibration durability test of the rake， a hole-edge crack appears and the natural frequency is reduced by 11.1%. The results show that when the vibration assessment test is carried out during the development of the rake， the structural damage of the rake body can be monitored in real time at the test site through the change of the natural frequency before and after the test.