Disclosed is a disposable safe injection needle, comprising a safe needle sleeve (1), a needle seat (2), a needle sheath (18) and a needle mating with each other the safe needle sleeve (1) comprises a socket (3) for trapping the needle, the needle sleeve (3) is provided thereon with a square sheet (6) for fastening the needle, and the lower portion of the sleeve (3) is provided with a bayonet (10) for fixing the needle sheath (18) the bottom of the sleeve (3) is provided with a cylinder (4) for connecting to the needle seat (2) the inner wall of the cylinder (4) is provided with internal frosting concave and convex grooves (9) the needle seat (2) is provided with a needle bonding section (11), a safe needle sleeve connecting section (12) and an inner conical connector end (13) the needle bonding section (11) is provided with a locating ring (15) for positioning the safe needle sleeve (1) and outside frosting concave and convex grooves (16) for preventing the safe needle sleeve (1) from easily sliding, wherein, after mating, the cylinder (4) is fitted inside the needle bonding section (11) of the needle seat (2). The safe injection needle has a simple and reasonable structure, and cannot be used twice so as to avoid cross-infections. It is difficult to scratch people, easy to manufacture, inexpensive and safe, such that a variety of injection syringes can all be equipped with the safe needle sleeve (1), and it thus has strong generality and very good practicability.Cette aiguille hypodermique de sécurité à usage unique comprend une gaine de securité (1), un moyeu daiguille (2), une gaine de protection de tête daiguille (18) et une tête daiguille, la gaine de sécurité (1) comprenant un manchon (3) destiné à recouvrir la tête daiguille, sur lequel manchon (3) vient une feuille carrée (6) et sur la partie inférieure duquel manchon (3) se trouve une baïonnette (10) destinée à fixer la gaine de protection de tête daiguille (18). En bas du manchon (3) et relié au moyeu dai
