An embodiment relates to a heat management device for a vehicle and a heat management method for a vehicle, which use a branch line and a flow control means to use heat generated from a battery module of a vehicle or a heat generated from an electrical component of the vehicle as a heat source for an air conditioning device installed in the vehicle. Therefore, the heat management device for a vehicle and the heat management method for a vehicle may improve heating performance and quality by selectively using waste heat from the electrical component module and the waste heat from the battery depending on the mode.