In order to solve the problem that poor dynamic performance of current gear measuring instruments seriously affects the stability, reliability and accuracy of measurement results, the researches on the dynamic design methods of gear measuring instruments were conducted and a dynamic design method combining finite element analysis and experiment modal analysis is put forward. First of all, the theoretical basis of dynamic analysis, the basic steps of finite element analysis and the basic principle of the experiment modal analysis are studied. Then, taking a certain gear fast measuring instrument as example, the finite element analysis and experiment modal analysis were carried out for the gear fast measuring instrument. Third, the measuring experiment was carried out on the gear fast measuring instrument, in which the gears with different precision were adopted, and the tests were carried out at different speeds. Finally, the vibration disturbance in the measurement experiments and the change of the vibration during the measurement process were analyzed. The experiment results show that the finite element analysis method can effectively improve the dynamic performance of the instrument in the design stage and can improve the dynamic performance index of the instrument fundamentally. The experiment modal analysis method can accurately obtain the actual dynamic performance index of the instrument after the instrument is manufactured, can effectively carry out the best working speed selection and further enhance the usage performance of the instrument. With the experiments, the correctness of finite element analysis and experimental modal analysis is verified, which provides a method for improving the dynamic precision of the gear measuring instrument and provide a viable way for reasonably using the measuring instrument.