The invention discloses an anus expander seat for surgery, which is used for expanding an anus and an anal canal. The anus expander seat comprises a hollow body and an externally expanding wide edge, wherein the wide edge is connected to the near end of the body. The anus expander seat is characterized in that: the body and the wide edge of the anus expander seat for surgery have winding drum structures; each winding drum structure comprises a positioning edge and an adjusting edge which selectively move or are fixed with each other; the outer wall of the adjusting edge is firmly attached to the inner wall of the positioning edge; and the adjusting edge can slide relatively to the inner wall of the positioning edge. The anus expander seat can gradually and controllably expand the anus andthe anal canal of a patient and can enable the sphincter of the anus to adapt to an amplitude opened by the anus expander seat before the anus expander seat is inserted, so that the phenomenon of anal fissure is avoided and the pain of the patient is relieved. The anus expander seat can be widely applied to surgical operation.