The medical instrument includes a long shaft member, a bendable bending portion, a support member deformable following a curved shape of the bending portion, a guide member extending from a distal end portion of the bending portion, And a linear member having a connecting portion connected to the guide member and inserted into the supporting member and pulling the guide member in accordance with a change in the curved shape. The center axis of the guide member is separated from the center axis of the support member. And the linear member protruding from the support member is connected to the connecting portion while being inclined with respect to the longitudinal axis of the guide member.この医療器具は、長軸部材と、湾曲可能な湾曲部と、前記湾曲部の湾曲形状に倣って変形可能な支持部材と、前記湾曲部の遠位端部から延設されたガイド部材と、前記ガイド部材に連結された連結部を有し、前記支持部材の中に挿入され、前記湾曲形状の変化に応じて前記ガイド部材を牽引する線状部材と、を備える。前記ガイド部材の中心軸は、前記支持部材の中心軸に対して離間する。前記支持部材から突出された前記線状部材は、前記ガイド部材の長手軸に対して傾斜して前記連結部に連結される。
