The blood circuit connector (100) comprises a tubular main body part (110) having a first opening end (120) and a second opening end (130) formed therein, and a detachable attachment A bottomed tubular stopper part (140) to be connected, and a connection part (150) connecting the main body part (110) and the plug part (140). The plug portion (140) includes a side wall portion (142) loosely fitted to the outer peripheral surface (111) of the first opening end (120) in a state of being attached to the first opening end (120). The connecting portion (150) includes a curved portion (155) bulging out in a direction away from the main body portion (110). In the attached state, loose fit between the side wall portion (142) and the outer peripheral surface (111) is released by pushing and extending the bending portion (155) in a direction to bring it close to the outer peripheral surface (111) of the main body portion , The plug portion (140) is detached from the first opening end (120).血液回路用コネクタ(100)は、第1開口端(120)および第2開口端(130)が形成された筒状の本体部(110)と、第1開口端(120)に着脱可能に取り付けられる有底筒状の栓部(140)と、本体部(110)および栓部(140)を接続する接続部(150)とを備える。栓部(140)は、第1開口端(120)に取り付けられた状態において、第1開口端(120)の外周面(111)に遊嵌する側壁部(142)を含む。接続部(150)は、本体部(110)から遠ざかる方向に向けて膨出する湾曲部(155)を含む。取付状態において、湾曲部(155)を本体部(110)の外周面(111)に近づける方向に押し込んで伸長させることにより、側壁部(142)と外周面(111)との遊嵌が解除され、栓部(140)が第1開口端(120)から取り外される。
