The endoscope 1 is provided on the operation unit 3, the insertion unit 2 that extends from the operation unit 3 and includes the distal end portion 5 and the bending portion 6, the distal end portion 5, and the space in the bending portion 6. A sealed first sealed space S1 and a second sealed space in which the observation optical system 9 and the illumination optical system 8 provided in the distal end portion 5 and sealed with respect to the space in the bending portion 6 are disposed. The communication passage 60 provided in the space S2 and the front end portion 5 and connecting the first sealed space S1 and the second sealed space S2, one end is connected to the first sealed space S1, and the other end is And an elongated tube member 10 having a longitudinal through-hole provided in the operation unit 3.内視鏡１は、操作部３と、操作部３から延出され、先端部５及び湾曲部６を備えた挿入部２と、先端部５に設けられ、湾曲部６内の空間に対して封止された第１の密閉空間Ｓ１と、先端部５に設けられ、湾曲部６内の空間に対して封止された観察光学系９及び照明光学系８が配設される第２の密閉空間Ｓ２と、先端部５に設けられ、第１の密閉空間Ｓ１と第２の密閉空間Ｓ２とを連絡する連絡通路６０と、一端部が第１の密閉空間Ｓ１に連結され、他端部が操作部３内に設けられる細長で長手方向貫通孔を有する管部材１０と、を具備する。
