Aiming at the problems of velocity loss of multi-wedge belt drive system in the process of operation,the multi-wedge belt drive speed loss test bench of two same size pulleys is established,the influences of the load torque,input speed,belt pre-tension,pulley diameter and belt length on belt velocity loss are obtained by using the multi-wedge belt drive test bench.The results show that increase the system load torque,reduce the input speed,belt pre-tension,pulley diameter and belt length,the multi-wedge belt drive velocity loss will be increased.The experimental study is conducted based on the multi-wedge belt drive system of key parameters,the influence of relevant parameters on system velocity loss is got,it can provide a certain reference for optimization design of the follow-up multi-wedge belt drive system.