A division type mechanical seal includes a through hole portion formed over two divided sealing rings so as to go over divided contact faces of the two divided sealing rings adjacent to each other in the circumferential direction, and a coupling tool inserted into the through hole portion to couple the two adjacent divided sealing rings. The coupling tool includes a bolt, a nut, and a tube fitted to a shaft portion of the bolt, and the tube is compressed in the axial direction and expanded in the outer diameter direction when the two adjacent divided sealing rings are coupled by fastening the nut.