Abstract: The instruments installation and calibration of the muhibeam sounding system are briefly introduced and the influence factors of the muhibeam sound system are analyzed. The multibeam sounding system and other surveying equipments are used to monitor the scouring protection work of the main pylon pier of the Sutong Bridge. Monitored results show that the system can meet the demands of guidance, surveying and acceptance of the scouring protection work of the Sutong Bridge.