The invention discloses an injector for anesthesia. The injector comprises an injection tube, wherein a scale plate is fixedly arranged at the top of the injection tube; a needle is fixedly connected to one end of the injection tube, and an opening is formed in the other end of the injection tube; a holding handle is arranged at the top of the opening of the injection tube; a No.1 piston is arranged inside the injection tube; the inner wall of the injection tube is movably connected to the right end of a first push rod by virtue of the No.1 piston; the left end of the first push rod penetrates through the opening and extends outside the injection tube; the left end of the first push rod is fixedly connected to one side of the first handle; and a groove is formed in the other side of the first handle. By setting a fixing device, the injector for anesthesia can achieve an effect of fixing the injection tube; by setting fixed teeth and an anti-slip layer inside the fixing device and by setting the scale plate, an effect of controlling the inserting depth of the needle is achieved; and by setting a pneumatic chamber, an effect of exhausting the injection tube is achieved.