The invention relates to an injection device (1, 101) having a housing (2) and a metering element (18) mounted in the housing (2) in a rotatable manner and in a fixed manner in the direction of a central longitudinal axis (50). The metering element (18) is connected via a first threaded connection (19) to an injection sleeve (17), which is rotationally fixed to the housing (2) and is held in a movable manner in the direction of the central longitudinal axis (50). When the injection liquid dose to be ejected is set, the metering element (18) rotates relative to the housing (2), and the injection sleeve (17) moves in the distal direction (30) on the basis of the first threaded connection (19). When the set injection liquid dose is ejected, the injection sleeve (17) moves in the proximal direction (31), and the metering element (18) rotates in the opposite direction on the basis of the first threaded connection (19). The aim of the invention is to allow an automatic injection of injection liquid. This is achieved in that the injection device (1, 101) has a spring (9), a first end (70) of which is supported on the injection sleeve (17) and a second end (71) of which is supported on the housing (2), and when the injection liquid is ejected, the spring moves the injection sleeve (17) in the proximal direction (31), thereby causing the set injection liquid dose to be ejected.
