To provide a machine element part which can improve the lubricating component-holding ability of a foamed solid lubricant holding the lubricating component, can control the oozing amount of the lubricating component to a necessary minimum amount, is excellent in the compatibility in initial lubrication, has a long life, and can respond to the demand of cost reduction.

This machine element part has a sliding surface on which a coating film is formed by a surface treatment and contains a foamed solid lubricant containing a lubricating component in a foamed, cured and porous resin on a sliding portion containing the sliding surface. A constant velocity universal joint as an example comprises an inner member 1, an outer member 2, a track groove 3 on the inner member side, a track groove 4 on the outer member side, a steel ball 5, a cage 6, a shaft 7, a boot 8, a foamed solid lubricant 9, a coating film 10, and other attachments. The foamed solid lubricant 9 is disposed close to the steel ball 5. The coating film 10 is formed on the inner diameter surface 6a of the cage.