The invention relates to injection device, which device comprises an outer housing (1), a syringe body (10) and a needle shield (30). Both the syringe body (10) and the needle shield (30) are telescopically movable mounted to the housing (1) such that the needle shield (30) is movable relatively to the housing (1) between a first position and a second position, and the syringe body (10) is movable in relation to the housing (1) between an extended position and a retracted position.