The endoscope 1 is provided in the operation unit 3 and has an operation shaft 32 and covers an outer periphery of the operation shaft 32 and an operation lever unit 30 that can adjust the bending angle of the bending unit 7 in conjunction with the tilting operation. An exterior cover 33 formed in a cross-sectional staircase shape, which is watertightly fixed to the operation unit 3 and has deformable portions 33a and 33c and flange deformable portions 33b and 33d having a predetermined angle with respect to the hardly deformable portions 33a and 33c. It is equipped with.内視鏡１は、操作部３に設けられ、操作軸３２を有して傾倒動作に連動させて湾曲部７の湾曲角度を調整可能な操作レバー部３０と、操作軸３２の外周を覆うように操作部３に水密固定され、難変形部位３３ａ，３３ｃと難変形部位３３ａ，３３ｃに対して所定の角度を有する昜変形部位３３ｂ，３３ｄを有した断面階段形状に形成された外装カバー３３と、を備えている。
