A lubricant can be evenly applied onto raceway faces or raceway grooves of a rail even when fixed to a horizontal, vertical, tilted, or ceiling surface. One or a plurality of embedding portions 26e having a recess or a hole is formed in a member body 26 straddling the rail R. An impregnation holding member 30 holding a lubricant is embedded in the embedding portion. The lubricating member supplies the impregnating lubricant onto the rail raceway faces while making contact with them. Even when the rail is fixed to a horizontal, vertical, tilted or a ceiling surface, the embedding portion of the member body straddling the rail has at least a part maintained in position at a level equal to or higher than the level of at least a part of one of the raceway sections 21a, 21b of the rail located higher relative to the other raceway section.