Novel medicine injection device for endoscope

The utility model discloses a novel medicine injection device for an endoscope. The novel medicine injection device comprises a needle cylinder, a piston rod, a needle head and an extension tube for extending the whole device, the piston rod is sleeved in the needle cylinder; one end of the extension tube is detachably connected with the needle cylinder, and the other end is fixedly connected with the needle head; a movable chuck is arranged on the side wall of the extension tube, the movable chuck is connected with the extension tube in a sliding mode, and a first groove used for allowing the movable chuck to be inserted is formed in the side wall of the needle cylinder. The extension tube is arranged, and the length of the extension tube is 30-40 cm, so that an injector can conveniently pass through the long tube of the poking card to puncture and inject medicine; and the length of the needle head is 4 mm, so that the puncture depth can be conveniently controlled during puncture only by completely puncturin