In order to further enhance the application effect of permanent magnet synchronous motor (PMSM) in energy-saving subway, a speed control method of energy-saving PMSM in subway based on fuzzy PID is proposed. By adding a fuzzy controller before the PID controller, the speed fuzzy PID controller of permanent magnet synchronous motor is constructed. The input of the controller is the speed error and the error change rate, and the speed adjustment parameters are output after fuzzy, reasoning and clear processing to complete the speed control. The model was established and tested by Matlab software. The results show that the speed change is smoother, the torque output is more gentle, and the current waveform is more stable in the case of the sudden change of the torque of the permanent magnet synchronous motor; the speed of the permanent magnet synchronous motor can reach a stable state in the shortest time without overshoot in the case of the jump and sudden drop of the speed, and the speed control accuracy is higher.