The invention discloses a pistol-type circumcise anastomat with an improved staple cartridge protective cap. The pistol-type circumcise anastomat comprises a pistol body and a pistol drive mechanism, wherein the pistol body is composed of a tube-shaped body part, a main shell boy and a handle part, a plurality of reinforcing ribs are arranged on the inner surface of a fixing barrel of the staple cartridge protective cap, distributed at intervals along the circumferential direction of the fixing barrel, and are parallel to the axis of the fixing barrel, one ends of the reinforcing ribs are connected with an annular bulge, the other ends of the reinforcing ribs are connected with an annular baffle plate, when the fixing barrel sleeves the periphery of the end part of a ring body of a staple cartridge ring, the annular bulge enables the sleeving to be very firm, and the plurality of reinforcing ribs enable the fixing barrel to be firmer and durable. Due to the adoption of the non-closed structural form, the annular baffle plates have certain toughness, so as to be protected from being damaged when the fixing barrel deforms.