Abstract: A joint has a plurality of synthetic resin hollow tubes inserted a plurality of resin-coated steel pipes which are formed by applying a coating resin on a surface of a thin wall steel pipe and are formed with at least one pair of fitting ribs extending in an axial direction on the coating resin for holding an edge of a partitioning body, in order to connect the resin-coated steel pipes in an intersecting fashion. The joint also includes slits which permit a pair of fitting ribs of the resin-coated steel pipes therethrough, are formed on reentrant side of at least adjacent two hollow tubes among a plurality of hollow tubes at positions in one plane extending across respective axes of the hollow tubes and extending over the entire length, and cover ribs which are formed integrally with the hollow tubes and extending along both sides of the entire length of the slits for covering outer side surfaces of a pair of fitting ribs of the resin-coated steel pipe.