The invention relates to a stern roller for a ship. The stern roller for the ship comprises a roller body and a reel. The reel is coaxially connected with the interior of the roller body in a penetrating mode and welded through a plurality of radial reinforcing plates and a plurality of axial reinforcing plates. The stern roller for the ship is characterized in that the reel comprises a shaft pipeand two end shafts, the two end shafts are welded to the two ends of the shaft pipe to form a through lone shaft body, one ends of the end shafts are welded to the interior of the roller body, the other ends of the end shafts stretch into a watertight cabin, and are supported in a water lubricating bearing through a stainless steel sleeve pipe, and the water lubricating bearing is positioned on the wall of the watertight cabin through a reinforcing rib plate.