The present invention provides an instrument for anorectal surgery, comprising a hollow main body, a suture junction disposed at a rear end of the main body and an inserting guider disposed at a front end of the main body. At an operating position, all or part of mucosa and tissues can get through the main body. At least one opening is made in the wall of the main body, and all or part of the mucosa and tissues can get into a hollow interior of the main body through the opening. Because of the openings on the wall of the main body, the present invention can be operated to perform the anorectal surgery of local and non-annular cutting, which facilitates a quick surgical operation, further allays the pain of the patients, and a better operation effect is obtained.