In order to accurately control the shortening of friction welding under the condition that the spindle speed of C32 friction welding machine was determined, the material was maximized utilized under the condition of forming a good welded joint, a closed-loop control system of friction welding machine based on PID was designed. The simulation analysis of the PID parameters of the closed-loop control system were done in AMESim software, and the simulation results were verified experimentally on the C32 friction welder. The results show that under the condition of determining the spindle speed, the closed-loop control of the friction welder under the PID algorithm can better guarantee the superior performance of the weldment under the premise of accurately controlling the shortening of friction welding.