To enable an anus treatment apparatus, having an insertion rod for insertion into the rectum from the anus and a heating plate locking the insertion rod and pressed against portions around the anus, to be inserted into the anus while the patient is sitting, so that the patient can be treated while sitting.

This chair is so designed that an anus treatment apparatus, having an insertion rod 33 for insertion into the rectum from the anus and a heating plate 34 locking the insertion rod 33 and pressed against portions around the anus, is mounted on the chair. In this case, the chair has a seat plate 2 having a releasable part 3 located beneath and in front of the anus when the patient is seated, and the releasable part 3 of the seat plate 2 is provided with a holding means 12 for holding the anus treatment apparatus.