Active reflector technology plays an important role in the development of radio telescopes. In order to improve the realtime surface detection in active reflector technology and reduce the detection errors caused by environmental factors, an active reflector surface monitoring research platform is established. A calculation and detection method of active reflector surface using distance measuring sensor is proposed. First, the active reflector datum surface is determined, and secondly, the panel motion is regarded as rotating motion. Rodrigo rotation formula is used to get the rotation matrix of the panel. Finally, the current position and attitude of the panel are calculated by using the rotation matrix of the panel. The simulation results show that the method is feasible, and the timeconsuming calculation of panel position and attitude at 1 625 nodes is 5 070 ms, which can improve the realtime performance of surface detection, provide reference for improving the operation accuracy of active reflector and achieve better performance index of radio telescope using active reflector technology.