Abstract: The invention relates to motor vehicle heating device with a burner, to which combustion air is supplied via combustion air inlet openings by means of a fan and to which furthermore fuel gas is supplied via a fuel gas supply line, combustion air and fuel gas entering on the intake side of the fan. It is provided according to the invention for a simpler structure and good mixing of the fuel gas/combustion air mixture that entry of fuel gas is controlled by means of a valve or switch controlled by the negative pressure of the fan. Fuel gas is supplied in doing so, preferably, with a negative pressure which is less than atmospheric pressure. For especially simple control of gas supply, there is a membrane which causes the fuel gas supply line to close when the fan stops.