To provide a small-sized medical treatment device equipped with a tip part such as a grip forceps used for surgery, and a surgical system equipped with the medical treatment device.SOLUTION: The medical treatment device includes an end effector, a wrist member, a shaft, a first pulley, and a second pulley. A first pulley part included in the end effector is rotatably attached to the wrist member via a first connection part, and is disposed on a first end side of the first connection part. The first pulley is attached to the wrist member, and a rotational axis of the first pulley crosses a surface including a first axis stipulated by the first connection part and a shaft axis, and is arranged on a second end side opposite to the first end of the first connection part as compared with a groove formed in the first pulley part.SELECTED DRAWING: Figure 5【課題】手術に用いられる把持鉗子などの先端部を備える医療用処置具であって、小型の医療用処置具、および当該医療用処置具を備える手術用システムを提供する。【解決手段】医療用処置具は、エンドエフェクタと、手首部材と、シャフトと、第１プーリと、第２プーリとを備え、エンドエフェクタに含まれる第１のプーリ部は、第１連結部を介して手首部材に回転可能に取り付けられ、かつ第１連結部の第１端側に配置され、第１プーリは、手首部材に取り付けられ、第１プーリの回転軸は、第１連結部により規定される第１軸、およびシャフト軸を含む面と交差し、かつ第１のプーリ部に形成され溝よりも、第１連結部の第１端と反対側の第２端側に配置される。【選択図】図５
