A battery temperature regulating device is provided with a low temperature heat exchanger configured to allow heat exchange with the air conditioning system, a battery temperature regulating unit configured to allow heat exchange with the low temperature heat exchanger so as to regulate the temperature of the battery to approach a target temperature, and a control unit configured to control the battery temperature regulating unit. In the case where the charging is performed from the power supply external to the vehicle, the control unit determines whether or not it is necessary to accumulate heat in the battery, and in the case where it is determined that the heat accumulation is necessary, the control unit sets the target temperature of the battery during charging higher than that in the case where it is determined that the heat accumulation is unnecessary.