A battery warm up system according to the present disclosure includes an open signal receiving unit to receive a door open signal for opening a door of a vehicle, a temperature measuring unit to measure a temperature of a battery pack connected to a starter of the vehicle, a control unit to output a forced discharging start signal by referring to information associated with the temperature measured by the temperature measuring unit when the door open signal is received by the open signal receiving unit, and a forced discharging circuit unit to force a plurality of battery modules constituting the battery pack to be discharged in response to the forced discharging start signal.