The living body observation system includes a light source device that supplies a first illumination light including a plurality of wavelength bands and a second illumination light including a plurality of wavelength bands different from the first illumination light, and illumination light. An image sensor that receives light from a subject illuminated by each of a plurality of pixels having different sensitivities to generate an image signal, and a sensitivity to light in a predetermined wavelength band from the image signal of each color component generated by the image sensor Is a color separation processing unit that separates an imaging signal corresponding to a color component obtained when imaging light of a predetermined wavelength band with the largest pixel among a plurality of pixels, and an imaging signal input to the color separation processing unit Includes a control unit that performs different color separation processing in the case of an imaging signal corresponding to the first illumination light and in the case of the imaging signal corresponding to the second illumination light.生体観察システムは、複数の波長帯域を含む第１の照明光と、第１の照明光とは異なる複数の波長帯域を含む第２の照明光と、を切り替えつつ供給する光源装置と、照明光により照明された被写体からの光を感度の異なる複数の画素毎に受光して撮像信号を生成する撮像素子と、撮像素子により生成された各色成分の撮像信号から、所定の波長帯域の光に対する感度が複数の画素の中で最も大きな画素で所定の波長帯域の光を撮像した際に得られる色成分に対応する撮像信号を分離する色分離処理部と、色分離処理部に入力される撮像信号が、第１の照明光に対応する撮像信号である場合と、第２の照明光に対応する撮像信号である場合と、において異なる色分離処理を行わせる制御部と、を有する。
