While ensuring adequate light distribution and brightness, to suppress flare and halation, it performs a good observation. Provided at the distal end of the insertion portion of the endoscope apparatus, an observation optical system for observing an observation target, provided in the insertion portion, illuminating the same field of view and light distribution of the illumination light emitted from the light source to an observation target and comprising a plurality of illumination optical systems, and, among the plurality of illumination optical systems, the far distance from the widest distribution light observation optical system than the illumination optical system of the illumination optical system is most narrow light distribution, the following conditions to provide an endoscope apparatus that satisfies the equation. 0.6 S f W / W f S 1.0 (1) However, f W is the focal length of the illumination optical system of the most wide light distribution, f S is the focal length of the illumination optical system of the most narrow light distribution, W is the outside diameter of the lens located closest to the object side surface of the illumination optical system of the most wide light distribution, S illumination optical system of the most narrow light distribution is the outer diameter of the lens is located in the most object side surface of.十分な配光と明るさを確保しながら、フレアやハレーションを抑制し、良好な観察を行う。 内視鏡装置の挿入部の先端に設けられ、観察対象を観察するための観察光学系と、挿入部に設けられ、光源から出射された照明光を観察対象に配光して同一視野を照明する複数の照明光学系と、を備え、複数の照明光学系のうち、最も広配光の照明光学系が最も狭配光の照明光学系よりも観察光学系からの距離が遠く、以下の条件式を満たす内視鏡装置を提供する。 0.6≦|φSfW/φWfS|≦1.0 ・・・ (1) 但し、fWは最も広配光の照明光学系の焦点距離であり、fSは最も狭配光の照明光学系の焦点距離であり、φWは最も広配光の照明光学系の最も物体側面に位置するレンズの外径であり、φSは最も狭配光の照明光学系の最も物体側面に位置するレンズの外径である。
