Cover plate with temporary protection function and ship rudder blade

The utility model relates to the technical field of ship construction, in particular to a cover plate with a temporary protection function and a ship rudder blade. The cover plate with the temporary protection function comprises a cover plate piece which is of a plate-shaped structure and used for covering the rudder blade hole; the face, facing the rudder blade hole, of the cover plate piece is of a curved surface structure so as to be attached to the rudder blade hole. The fixing piece is rotationally connected with the cover plate piece, and the end, capable of extending into the rudder blade hole, of the fixing piece forms a bent fixing part; and the fixing part is rotated to enable the bending direction of the fixing part to extend towards the hole wall of the rudder blade hole, so that the rudder blade hole is clamped between the cover plate part and the fixing part. The rudder blade hole can be temporarily sealed, the cover plate can be fixedly connected with the curved-surface rudder blade hole and at