The invention relates to an injection device (1), which comprises a support housing (2), an activating sleeve (9), a cartridge (3) containing a medicine (14), a first drive unit (4), a safety device (5), a needle arrangement (6), a needle protection element (7) and a second triggerable drive unit (8), whereby the latter moves the needle protection element (7) from the non-effective position into the position covering one needle end (21) of a cannula (20). The support housing (2) is surrounded over most of its longitudinal extension between its distal and proximal end (11, 12) by the activating sleeve (9), whereby the needle protection element (7) with the second drive unit (8) cooperating therewith is arranged radially between the support housing (2) and the activating sleeve (9), as viewed in axial cross section.
