Abstract: There is an object to provide a technique of forming a proper abrasion resistance layer by a thermal spraying and fusing of a self fluxing alloy. The object may be solved by cutting the pipe body along a curved face that is perpendicular to a plane including a central axis of the pipe body and that extends not to cross the inlet hole and the outlet hole but to include a part of the central axis. Thus the pipe body is divided into a first partitioned part having at least one of the inlet hole and the outlet hole, and a second partitioned part. An abrasion resistance layer is then formed on the inner surface of at least the outer bent portion of the pipe body by a thermal spraying and fusing of a self fluxing alloy. Thereafter, the first partitioned part is fitted into the second partitioned part for welding to obtain a bent pipe according to the present invention.