To provide an endoscope apparatus capable of cleaning the surface of lenses mounted in a distal end side of the insertion section by changing the jetting direction of sprayed fluid mixture without the force of the sprayed fluid mixture being reduced.SOLUTION: An endoscope apparatus 100 comprises: an endoscope 1 having an insertion section 2； and a cleaning sheath 10. The cleansing sheath comprises: a multi-lumen tube 20 and a distal end structure 30 which are mounted to the insertion section 2 having a first conduit line 22 and a second conduit line 23 connecting to an opening 11 which jets out a fluid； a first fluid tube 51 connecting to the first conduit line 22； a second fluid tube 52 connecting to the second conduit line 23； a gas feeding pump 73 for feeding a gas to the opening 11； a liquid feeding pump 83 and a liquid feeding tank 82 for feeding a liquid to the opening 11； and a switching unit 60 for switching between a first fluid feeding state which feeds the gas to the first fluid tube 51 and the liquid to the second fluid tube 52 and a second fluid feeding state which feeds the gas to the second fluid tube 52 and the liquid to the first fluid tube 51.SELECTED DRAWING: Figure 1【課題】噴霧状態の混合流体の勢いを低下させること無く噴出方向を変化させて挿入部の先端側に配置されたレンズ表面の洗浄が可能な内視鏡装置を提供する。【解決手段】内視鏡装置１００は、挿入部２を有する内視鏡１と、流体を噴出させる開口１１に通じる第１管路２２及び第２管路２３を有する挿入部２に装着されるマルチルーメンチューブ２０及び先端構成部３０と、第１管路２２に通じる第１の流体チューブ５１と、第２管路２３に通じる第２の流体チューブ５２と、開口１１に気体を供給する送気ポンプ７３と、開口１１に液体を供給する送水ポンプ８３及び送水タンク８２と、気体を第１の流体チューブ５１に供給して液体を第２の流体チューブ５２に供給する第１の流体供給状態、または、気体を第２の流体チューブ５２に供給して液体を第１の流体チューブ５１に供給する第２の流体供給状態、に切り換える切替部６０と、を具備する洗浄シース１０と、を備える。【選択図】図１
