Abstract: For the stability test requirements of precision optical tracking system ，we presented a dynamic testing method of stability accuracy. According to the optical auto-collimation principle，we utilized the CCD array detector combined with the computation for center of image to realize the dynamic test , and we required the test results of stability accuracy by this device. Experiments results show that for the 50 rad level two-axis two-frame system,the tested stability accuracy is up to 48 rad by our method.