The invention relates to a method for checking the perpendicularity between the adjacent axes of a dual-axis rotary inertial measurement device by using an accelerometer, including the following steps: (1) determining the composition of perpendicularity error, wherein beta is the perpendicularity between an inner frame axis and an outer frame axis; (2) leveling a dual-axis rotary inertial measurement device; (3) setting the horizontal axis to 0 degrees, and obtaining A; (4) setting the horizontal axis to 180 degrees, and obtaining B; and (5) obtaining the perpendicularity beta between the inner frame axis and the outer frame axis through calculation. The practical engineering application problem about the perpendicularity between the horizontal axis and the azimuth axis of a dual-axis rotary inertial measurement device is solved, and the applicability of a dual-axis rotary inertial measurement device shafting test method is guaranteed. By using the method of the invention, the dependence of measurement on external means can be reduced, the cost can be reduced, and the efficiency can be improved. The method is of promotion value.