The invention relates to a heating device (10) for a vehicle, comprising: a flow path (14, 16, 20, 22, 24) for a liquid heat transfer agent; an electric heating device (34) for generating heat and for releasing generated heat to the heat transfer agent on a heating portion (20) of the flow path; and an electronic controller (26) for controlling a heat output of the heating device. The controller (26) is provided with a heat releasing body in order to release waste heat of the controller (26) to the heat transfer agent on a preheating portion (16) of the flow path upstream of the heating portion (20). The invention likewise relates to a method for cooling the controller.