In view of difficulty in high-precision test of time and position in rocket sled test, shading plate position and time testing method was presented. Based on the method, overall design idea, photoelectric component design, sled borne data recorder design, telemetric system design, shading plate design and layout method, measurement methods from the shading plate, target data processing method and other aspects were discussed in this paper. Designers developed related products, tests prove that the test data obtained is good. The method can achieve high testing precision, and can meet inertial measurement unit function and accuracy test, it is prospective.