Abstract: The present disclosure provides a stapler, including a shell, an ejector plate pin, a cartridge pin, an anvil pin, an unlocking pin, an ejector plate ring, a cartridge ring and an anvil ring, where the cartridge pin is between the ejector plate pin and the anvil pin; the ejector plate ring, the cartridge ring and the anvil ring all include a first half ring and a second half ring; hinged ends of the first half rings and the second half rings are rotatably connected, and fixed ends of the second half rings of the ejector plate ring, the cartridge ring and the anvil ring are connected to the front ends of the ejector plate pin, the cartridge pin and the anvil pin, respectively. The present disclosure adopts a brand-new concept of eversion anastomosis, and ensures the smoothness of a lumen after anastomosis.