Abstract: To improve the performance and operation accuracy of compliant mechanisms,a lot of work needs to be done to further the study of frequency characteristics analysis of compliant mechanisms.The dynamic equation of compliant mechanism based on the finite element method is developed,and the natural frequencies and modes are derived at first.A method for calculating the sensitivity of natural frequency is then presented. The numerical example result shows that the design parameters have impact on the frequency characteristics of compliant mechanisms,and also indicates that the method for frequency characteristics analysis of compliant mechanisms is effective and efficient.