A battery warm up system according to the present disclosure includes a battery state measuring unit to measure a state of charge (SOC) of each module of a battery pack of a vehicle, a control unit to optionally output a forced discharging start signal and to output a balancing start signal, a forced discharging circuit unit to force at least one battery module among a plurality of battery modules of the battery pack to be discharged in response to the forced discharging start signal, and a balancing unit to balance the SOC of each of the battery modules in response to the balancing start signal.