To surely prevent leakage of emission gas and the like from an engine from a joint main body and to improve an appearance.

A joint main body 3 is formed of a single cylindrical molded body. The main body 3 is formed into a taper gradually tapering down from the upstream side to the downstream side as a whole. An exhaust pipe connection port 7, to which two exhaust pipes 2 are connected together, is formed in the upstream end of the joint main body 3. A pair of throttle parts 8a, 8b drawn by press molding are formed in the upper part and the lower part of the width directional central part of the exhaust port 7. In a manufacturing method of the joint main body 3, a molding material is spread around its axial line in an expansion process, and the spread molding material is pressed in its radius direction in a pressing process, and the spread part, in the molding material is drawn in the radius direction.