A tube connecting structure (1) according to the present invention comprises a first connector (2) and a second connector (3) which are fitted to each other, wherein the first connector (2) comprises an outer cylinder A communicating portion (23) forming a liquid passage (23c) enabling the liquid to flow in a mated state, and an annular valve body (24) provided around the communicating portion (23) and sealing the outer tube opening portion (22a) in a non-Wherein the second connector (3) comprises an inner cylinder (32) for pushing the annular valve body (24) in a fitted state, an inner cylinder (32) for sealing the inner cylinder opening (32a) when not fitted, An inner valve body which is pushed by a communicating portion which enters into the inner cylinder (32) via the inner cylinder opening (32a) in the assembled state, and an inner valve body which is provided at least on the inner peripheral surface of the inner cylinder opening (32a) And a first seal member (41) inserted through the inner tube opening (32a) and sealing the space between the communicating portion (23) and the inner tube opening portion (32a) in a liquid-tight manner, wherein the communicating portion ), A liquid passage (23 c) is provided in a portion that enters the inside of the inner cylinder (32) in a fitted state.本発明に係るチューブ接続構造(1)は、互いに嵌合する第一コネクタ(2)と第二コネクタ(3)とで構成され、第一コネクタ(2)が、外筒(22)と、嵌合状態で液体を流通可能とする液体通路(23c)を形成した連通部(23)と、その周囲に設けられ、非嵌合状態では外筒開口部(22a)を密閉する環状弁体(24)とを備え、第二コネクタ(3)が、嵌合状態では環状弁体(24)を押し込む内筒(32)と、非嵌合状態では内筒開口部(32a)を密閉するとともに、嵌合状態では内筒開口部(32a)を介して内筒(32)内に進入する連通部により押し込まれる内側弁体と、内筒開口部(32a)の内周面に少なくとも設けられ、嵌合状態で、内筒開口部(32a)に挿通され連通部(23)と内筒開口部(32a)との間を液密にシールする第一シール部材(41)とを備え、連通部(23)の、嵌合状態で内筒(32)の内側に入り込む部分に、液体通路(23c)を設けたことを特徴とする。
