An instrument hose support device comprising: an instrument holding device holding an instrument ; a rod that supports an instrument hose of the instrument ; a groove that intersects the distal end of the rod and that forms a movable axis (X) being the central axis of the groove; a pulley support portion that is composed of a first member and a second member , wherein the first member is composed of a first support portion that is supported by a distal end of the rod, a first arm portion that extends from the first support portion toward a pulley , and a first support shaft that is formed on the first arm portion and inserted through a shaft of the pulley , and wherein the second member is composed of a second support portion that is fitted to the first support portion from a side opposite to the rod relative to the first member , a second arm portion that extends from the second support portion toward the pulley , and a second support shaft that is formed on the second arm portion , that is inserted in the shaft of the pulley , and that is fitted in the first support shaft , wherein the pulley support portion rotates freely and swings freely; a pulley that is supported by the pulley support portion and over which the instrument hose is looped, wherein the pulley swings freely around the movable axis (X) formed by the central axis of the groove ; and a shaft protrusion that is inserted into the groove; wherein a taper is formed in the shaft protrusion or in the groove to form a gap between the shaft protrusion and the groove, wherein the gap is configured to serve as the range of motion of the pulley support portion , and wherein one of the shaft protrusion and the groove is formed at the first support portion of the pulley support portion, and the other one of the shaft protrusion and the groove is formed at the distal end of the rod. an instrument holding device holding an instrument ; a rod that supports an instrument hose of the instrument ; a groove that intersects the distal end of the rod and that forms a movable axis (X) being the central axis of the groove; a pulley support portion that is composed of a first member and a second member , wherein the first member is composed of a first support portion that is supported by a distal end of the rod, a first arm portion that extends from the first support portion toward a pulley , and a first support shaft that is formed on the first arm portion and inserted through a shaft of the pulley , and wherein the second member is composed of a second support portion that is fitted to the first support portion from a side opposite to the rod relative to the first member , a second arm portion that extends from the second support portion toward the pulley , and a second support shaft that is formed on the second arm portion , that is inserted in the shaft of the pulley , and that is fitted in the first support shaft , wherein the pulley support portion rotates freely and swings freely; a pulley that is supported by the pulley support portion and over which the instrument hose is looped, wherein the pulley swings freely around the movable axis (X) formed by the central axis of the groove ; and a shaft protrusion that is inserted into the groove; wherein a taper is formed in the shaft protrusion or in the groove to form a gap between the shaft protrusion and the groove, wherein the gap is configured to serve as the range of motion of the pulley support portion , and wherein one of the shaft protrusion and the groove is formed at the first support portion of the pulley support portion, and the other one of the shaft protrusion and the groove is formed at the distal end of the rod. <EOS>