To prevent abnormal noises from a sealing device for a shaft of steering system by forming a large number of small recesses and protruding portions that can freely retain a lubricant on either peripheral surface of the inner peripheral surface of the insertion hole or the outer peripheral surface at the intermediate portion of the shaft that slidably contacts the inner peripheral surface.

Grease kept in a recess groove formed on an inner peripheral surface of an outer fitting portion 11 and a large number of small recess and protruding portions formed on the inner peripheral surface thereof or the like remains between an inner peripheral surface of an insertion hole 10 and an outer peripheral surface of a shaft such as an intermediate shaft 16 or the like for an extended period. Accordingly, sufficient amount of grease is supplied to a sliding portion of both peripheral surfaces for a long time. This makes it possible to prevent abnormal noise from generating in the sliding portion. Further, the outer peripheral surface of the intermediate shaft 16 and the inner peripheral surface of the outer fitting portion 11 closely contact with each other over the entire surfaces owing to a plurality of small recess and protruding portions, preventing contact of the entire surface. Therefore, friction resistance against the rotation of the intermediate shaft 16 at the inner side of an insertion hole 12 is reduced, and abnormal noise can be reduced more effectively.