Disclosed is a safety injection needle. An injection needle (1) consists of a needle hub (101) and a needle tube (102). The needle hub (101) is connected to a safety protective cover (2) by means of an elastic flip mechanism (4). Two symmetrically-distributed needle hub hooks (103) are provided on a side wall of the needle hub (101). Two symmetrically-distributed protective cover snaps (203) are provided in a hollow inner cavity of the safety protective cover (2). The two protective cover snaps (203) cooperates with the two needle hub hooks (103). Protective cover snap stoppers (204) are provided on outer sides of the two protective cover snaps (203). The injection needle employs the two needle hub hooks (103) which are disposed on the side wall of the needle hub (101) and cooperate with the two protective cover snaps (203) disposed in the inner cavity of the safety protective cover (2). The snap-fitting process of the protective cover snaps (203) and the needle hub hooks (103) is easy, simple and convenient, a required thrust is only about 0.5 N, and a single-hand operation can be achieved. The protective cover snap stoppers (204) disposed on the outer sides of the protective cover snaps (203) can effectively prevent disengagement of the protective cover snaps (203) from the needle hub hooks (103).
