TECHNICAL FIELD The present invention relates to a tubular body that securely maintains watertightness and airtightness between parts while securing a fixing strength of a connection part between an operation part and a multi-lumen tube and does not inhibit fluid flow in a sub-lumen of a multi-lumen tube For this purpose, a main lumen 12a and a sub-lumen 12b having an inner diameter smaller than that of the main lumen are provided along the longitudinal axis, and both lumens A first fixing member 13c having a mouthpiece 13g into which the base end portion of the main lumen is inserted and communicatively connected a first tube member A second fixing member 13d which is externally mounted on the first tube member and has a pressure contact portion which is urged against the mouthpiece portion via the first tube member, a connecting portion communicating with the sub lumen on the base end side of the press-And a flexible second tube body 15 having an extending portion extending from the connecting portion.本発明は、操作部とマルチルーメンチューブとの接続部位の固定強度を確保しつつ部品間の水密性及び気密性を確実に維持しかつマルチルーメンチューブのサブルーメンの流体の流通を阻害しないチューブ体の固定構造を提供することを目的とし、そのために、基端部と先端部とを有しメインルーメン12aとメインルーメンよりも内径が小さいサブルーメン12bとが長手軸に沿って内設され両ルーメンが基端部にそれぞれ開口する柔軟な第1のチューブ体12と、メインルーメンの基端部が挿入されて連通接続される口金部13gを有する第1の固定部材13cと、第1のチューブ体に外装されると共に第1のチューブ体を介して口金部に付勢される圧接部を有する第2の固定部材13dと、圧接部よりも基端側でサブルーメンと連通接続される接続部と接続部から延出される延出部とを有する柔軟な第2のチューブ体15とを備える。
