The medical connector (1) of the present invention has a length twice the distance between the center of the top face (11 f 2) of the valve body (11 f) and the end portion of the slit (11 e) furthest away from the center in the radial direction A tubular body (2a) having the following outer diameter and capable of being inserted into the slit (11e) and a tube body (2a) inserted into the other medical connector (10) when the male connector part (2) is connected to the closed type female connector part A restriction portion (2c) for restricting the insertion depth of the pipe body (2a) into the opening portion (11a) by abutting the slit (2c) when the male connector portion (2) is connected to the closed type female connector portion (11) A sealing portion which closely contacts the top face of the valve body and the top face of the top face wall surrounding the top face of the valve body and the closed female connector portion of the male connector portion, And a locking portion (2 d) for maintaining the connection state to the other end portion.本発明の医療用コネクタ（１）は、弁体（１１ｆ）の天面（１１ｆ２）の中心と該中心から径方向に最も離れたスリット（１１ｅ）の端部との間隔の２倍の長さ以下の外径を有しスリット（１１ｅ）に挿入可能な管体（２ａ）と、オスコネクタ部（２）を閉鎖式メスコネクタ部（１１）に接続したとき他の医療用コネクタ（１０）に当接して開口部（１１ａ）への管体（２ａ）の挿入深さを規制する規制部（２ｃ）と、オスコネクタ部（２）を閉鎖式メスコネクタ部（１１）に接続したときスリット（１１ｅ）を取り囲んで弁体（１１ｆ）の天面（１１ｆ２）又は天面壁（１１ｂ）の天面（１１ｂ２）に密着するシール部と、オスコネクタ部（２）の閉鎖式メスコネクタ部（１１）への接続状態を維持するロック部（２ｄ）とを備えている。
