An endoscope system includes an endoscope (2) and a high temperature and high pressure steam supplying unit for supplying high temperature and high pressure steam into an endoscope interior (45) and a channel (93) from outside of the endoscope (2). The channel member (93) which has one opening (44) at a distal portion (17) of an insertion portion (7) and other opening (26) at a portion other than the distal portion (17) while the portion other than the two openings described above is covered by an exterior member, is inserted into the endoscope. The endoscope has an exterior member opening (37) that communicatively connects the endoscope interior (45) covered by the exterior member to outside and a detachable filter (149) that is provided on the exterior member opening (37). The detachable filter (149) prevents entry of dust into the interior (45) and leakage of a lubricant agent of the interior (45) to outside of the endoscope.
