Safety injector includes a syringe, a push rod and a needle set. Push rod is movably worn in what syringe. Needle set is separably arranged what syringe front end. Wherein, push rod front end is equipped with the pushing post of an elastomer and a prominent what elastomer, when push rod front end is mobile toward needle set direction so that elastomer be pressurized and flexible deformation support what syringe, to make pushing post be pierced by syringe and push against needle set outward, to enable needle set separate what syringe.安全注射器包括一針筒、一推桿、及一針具。推桿可移動地穿設於針筒內。針具可分離地套設於針筒前端。其中，推桿前端設有一彈性體及一突出於彈性體的頂推柱，當推桿前端往針具方向移動，以使彈性體受壓而彈性變形地抵頂於針筒，從而使頂推柱穿出針筒並往外推抵針具，以令針具分離於針筒。
