Provided are a mantle tube whereby foreign matter adhering to an observation window of an endoscope can be removed by a simple operation and good visibility can always be maintained, and a surgery device for an endoscope. A fluid supply/discharge port (500) is provided for delivering washing water to the distal-end part of an endoscope insertion passage (306) through which an endoscope insertion part (102) is inserted in a mantle tube (300). When cleaning an observation window of the endoscope insertion part (102) inserted through the endoscope insertion passage (306), an operator can, through use of a positioning mechanism, set a distal-end face (114) in a positioning position determined in advance without withdrawing the endoscope insertion part (102) from the endoscope insertion passage (306). A recessed washing reservoir (502) communicated with the fluid supply/discharge port (500) is thereby formed from the distal-end face (114) of the endoscope insertion part (102) inside the endoscope insertion passage (306) at the distal end thereof. In this state, the washing water is supplied from the fluid supply/discharge port (500), washing water is retained by the washing reservoir (502), and foreign matter on the observation window is removed. The washing water retained by the washing reservoir (502) is then suctioned from the fluid supply/discharge port (500), and water droplets are removed from the observation window.Linvention concerne un tube manchon, grâce a laquelle des matières étrangères adhérant à une fenêtre dobservation dun endoscope peuvent être éliminées par une opération simple, et une bonne visibilité peut toujours être maintenue, et un dispositif de chirurgie pour un endoscope. Un orifice dalimentation/évacuation de fluide (500) est conçu pour distribuer leau de lavage à la partie dextrémité distale dun passage dinsertion dendoscope (306), à travers lequel une partie dinsertion dendoscope (102) est insérée dans un tube manchon (300). Lors du nettoyage
