A mechanical seal that prevents deposition of a degradation material generated on a sliding interface is to be provided. In a mechanical seal including a sleeve that rotates with a rotating shaft, a seal cover fixed to a housing, a rotating ring attached to the sleeve and a fixed ring attached to the seal cover and disposed in sliding-contact with the rotating ring via a sliding interface perpendicular to the rotating shaft scraping member is provided on the sleeve at a position close to an inner edge of the sliding interface so as to remove a degradation material from the inner edge of the sliding interface.