A fuel injection device for internal combustion engines having externally supplied ignition, which enables introducing fuel injection quantities into combustion chambers in a manner that is controlled precisely in terms of quantity and of the instant of injection. The fuel injection device includes a first magnet valve by which fuel at injection pressure is pre-stored in a reservoir chamber, and the pre-stored quantity is ascertained by measurement of the deflection stroke of a reservoir piston which defines the reservoir chamber. Once the pre-storing process is complete, the pre-stored fuel quantity is then delivered to the injection valve with the air of a second magnetic valve. All that the fuel injection pump needs besides the two magnet valves and a control unit is a pre-feed pump, which pumps fuel into a high-pressure reservoir, so that while making limited demands on the pump generating the high pressure, a simple and very precisely functioning fuel injection device is created.