The invention discloses a reverse serial connection control system and method for three direct-current motors. Eight IGBT modules of a four-phase inverter are connected in series two by two to form four bridge arms which are connected with the positive electrode and the negative electrode of a direct-current power supply in parallel; the three direct-current motors in reverse serial connection areconnected with the four bridge arms in series; the three direct-current motors pass through a speed sensor, a current sensor and a speed adjustment module in sequence and then are connected with a reference voltage synthesizer through a two-stage PI controller separately; the reference voltage synthesizer is connected with the four-phase inverter through a PWM pulse generation unit; the four-phase inverter is connected with the reference voltage synthesizer through a current adjusting module and a first-stage PI controller separately, and is connected to the PWM pulse generation unit throughthe reference voltage synthesizer; and pulse control signals generated by the PWM pulse generation unit are used for controlling on-off of the eight IGBT modules to drive the three current-current motors to run. By virtue of the reverse serial connection control system and method, four-quadrant operation of the three motors can be realized, the running direction and the operation speed of the motors can be changed, the energy of a motor feedback system can be sent back to the power grid, and the energy consumption is lowered.