To combine two principles of permitting a pressure-controlled injection process and a stroke-controlled injection process in one injector.

The injector for injecting fuel into a combustion chamber of an internal combustion engine houses a valve element 10 whose pressure is releasable by a control chamber 11, and a nozzle needle 29 whose pressure is releasable via another control chamber 26. A nozzle chamber 34 circumscribing the nozzle needle 29 around a pressure step 45 is loaded with high pressure via a casing-side nozzle inlet passage 30, 33. The injector 1 is, in a pressure side, pressure-controlled via the valve element 10 controlled as a three-port, two-position directional control valve, and on the other hand, in a leakage oil side, stroke-controlled via a two-port, two-position directional control valve 23. The valves 10, 13 and 23 are controlled by one common actuator 3 or independently of one another.