The invention provides a voltage balancing system for voltage balancing. The voltage balancing system includes an analog front end arranged in parallel with the cell group, a micro control unit communicating with the analog front end, a communication isolation module connected between the analog front end and the micro control unit, and a balancing module. The input of the balancing module is connected to the cell group to input the total voltage of the cell group. The output of the balancing module is connected to the micro control unit and the communication isolation module to output the operating voltage of the micro control unit and the communication isolation module.