A charging system using a motor driving system including a battery, an inverter configured to receive and convert DC power stored in the battery into three-phase AC power and to output the three-phase AC power to a motor when the motor is driven and the motor configured to generate rotation force using the three-phase AC power output from the inverter, may include a controller configured to control the inverter to boost a voltage of a neutral point of the motor and to output the boosted voltage to the battery, by determining duty values of switching elements in the inverter when external charging current is provided to the neutral point of the motor.