The invention relates to a method of producing medical devices, which has a step of forming a tubular body which has flexibility and long length, and is able to be inserted into a body cavity. The step of forming the tubular body has following steps: a step of preparing a first tubular body (multithread Coils (310)) which is configured by winding around spirally so that plurality of wires (311) are arranged in parallel state in winding axis direction a step of welding two or more wires together by melting partially each of two or more wires (311) adjacent in a first welding portion (312) which is extending in the cross direction with respect to the circumferential direction of the first tubular body a step of welding plurality of wires (311) together by melting partially each of plurality of wires (311) in a second welding portion (313) which has a ring shape around the first tubular body and a step of connecting one end of a second tubular body to the second weld potion so as to coupling the first tubular body with the second tubular body.本發明容易地將多條盤管連接於其他之管狀體。本發明之醫療機器之製造方法具有形成長條且具有可撓性、插入體腔內之管狀主體之步驟。形成管狀主體之步驟具有以下之步驟。準備藉由以複數根線材(311)成為在捲繞軸向上排列之並列狀態之方式螺旋狀捲繞而構成之第1管狀體(多條盤管(310))之步驟。在向相對於第1管狀體之周向之交叉方向延伸之第1熔接部(312)中,使相鄰之2根以上之線材(311)之各者部分熔融,藉此熔接該等2根以上之線材(311)彼此之步驟。在環繞第1管狀體之環形狀之第2熔接部(313)中,使複數根線材(311)之各者部分熔融,藉此熔接該等複數根線材(311)彼此之步驟。以於第1管狀體上連接第2管狀體之方式,將第2管狀體之一端連結於第2熔接部(313)之步驟。310‧‧‧多條盤管311‧‧‧線材312‧‧‧第1熔接部313‧‧‧第2熔接部313a‧‧‧第1部分313b‧‧‧第2部分320‧‧‧多條盤管331‧‧‧箭頭332‧‧‧箭頭333‧‧‧箭頭334‧‧‧箭頭341‧‧‧熔接點
