The invention discloses a dithering sensitivity-based assessment method for the dithering sensitivities of two-frequency mechanically-dithered laser gyroscopes, and belongs to the field of inertial navigation, guidance and control. The method comprises the steps that 1, the target dithering amplitudes of the two-frequency mechanically-dithered laser gyroscopes are set; 2, the driving voltage of the two-frequency mechanically-dithered laser gyroscopes is collected; 3, the actual dithering amplitudes of the two-frequency mechanically-dithered laser gyroscopes are collected; 4, the dithering sensitivities of the two-frequency mechanically-dithered laser gyroscopes installed on an inertial measurement unit under the different installation configurations are calculated; 5, the dithering sensitivities of the two-frequency mechanically-dithered laser gyroscopes under the different configurations are compared, and then the optimal installation configuration scheme of the inertial measurement unit with the two-frequency mechanically-dithered laser gyroscopes is obtained. When the method is used for designing the inertial measurement unit composed of the two-frequency mechanically-dithered laser gyroscopes, the configuration scheme with the most suitable dithering frequency and installation positions is selected, it is guaranteed that the inertial measurement unit can work in the best state, the using precision of the two-frequency mechanically-dithered laser gyroscopes is improved, and the service life of the two-frequency mechanically-dithered laser gyroscopes is prolonged.