To prevent a distortion from being generated in a metal member by constituting a molding connecting structure of an annular and a helical groove formed in both faces of the metal member, and an annular and a helical protruding strip which fit into the annular and the helical groove when a synthetic resin material is molded.

A circular ring-like runner R as a synthetic resin member is molded on the outer peripheral face of a bush M as a metal member, and both M, R are connected to each other with a mold connecting structure. In addition, an annular groove 2 is cut out on the outer peripheral face of the bush M and a helical groove 3 is formed by cutting in such a manner that one of its ends communicates with the annular groove 2 and it is long enough to make at least, a single circuit around the bush M. Further, an annular and a helical protruding strip 5, 6 are jutted out by molding pressure on the outer peripheral face of the bush M so that these protruding strips 5, 6 fit into the annular and the helical groove 2, 3 respectively when a runner R surrounding the bush M is molded. Thus it is possible to firmly cause the annular groove and the protruding strip 2, 5, and the helical groove and the protruding strop 3, 6 to be tightly engaged with each other and thereby, positively prevent both bush M and runner R from slipping to each other in the axial direction and the rotating direction.