A needle protection device detachably fixed to an injection appliance includes a needle, a needle holder from which a needle injection section of the needle projects distally and a needle connection section of the needle projects proximally, a distal needle protection element connected to the needle holder movable in the distal direction from a release position to a protection position and arranged behind the needle injection section in the release position and overlapping the needle injection section and distal end of the injection needle in the protection position, a proximal needle protection element connected to the needle holder movable from a release position and arranged behind the needle connection section into a protection position and overlapping the needle connection section and proximal end of the injection needle, and a blocking device which blocks movement of the proximal needle protection element from the protection position into the release position.