Abstract: An electro-fusion fitting includes a body, and a magnetic alloy member which is continuous in the axial direction is embedded in the vicinity of a joint surface of the body. A shield member is arranged on the outer surface of the body in a portion where a cold zone is to be formed. The joint surface of the body and a joint surface of a member to be joined are brought into contact with each other. When a high frequency current is applied to the magnetic alloy member from a high frequency power supply by electromagnetic induction in this state, the magnetic alloy member generates heat, so that the body and the member to be joined are fused, and joined to each other. Since the shield member shields the electromagnetic induction, the magnetic alloy member in a portion where the shield member is provided does not generate heat, so that the cold zone is formed in the portion.