A novel measurement method for the dynamic characteristic of ring laser gyroscope was proposed, based on a new laser Doppler vibrometer. The research on the dynamic characteristic of Ring Laser Gyroscope as a contacting system has important implications. A PZT angular vibration table was used to generate sine angular vibration, and the related measurement of the Ring Laser Gyroscope and the laser Doppler vibrometer were compared. The related experiments were conducted. Experimental results show that the property of transfer function of mechanism is a major factor affecting Ring Laser Gyroscope measure distortion under high frequency. The measurement of Ring Laser Gyroscope is accurate under low frequency and the amplitude frequency curve has been taken.