Self-destruction injector with retractable needle head

The utility model discloses a safety self-destruction injector with a retractable needle head. A self-destruction device is arranged in the injector. The safety self-destruction injector comprises a pull-back head, a conical mesh hole and an extraction rod, wherein the pull-back head is positioned in a needle holder; the needle head is bonded in a tube body at the front end of the pull-back head; the inner wall of a tube body at the bottom end of the pull-back head has a frustum-shaped structure; the outer wall of the tube body at the bottom end of the pull-back head is provided with a first bump; the conical mesh hole is formed in an injection barrel inner wall at the connecting segment of an injection barrel and the needle holder, and is pressed against the bottom end of the pull-back head; the extraction rod is arranged at the front end of a push rod; one end, which faces the needle holder, of the extraction rod consists of a hollow cylindrical outer tube and a frustum-shaped bump arranged in the outer tube; the inner wall of the outer tube is provided with a first groove matched with the first bump. According to the safety self-destruction injector provided by the utility model, the extraction rod sleeves the pull-back head to drive the pull-back head and the needle head to retract into the injection barrel, and self-destruction is realized by breaking the push rod from an annular groove.