An endoscope system 1 according to the present invention includes a light source device 4, an endoscope 2, and a processing device 3. The light source device 4 sequentially emits illumination light of different colors in accordance with a frame cycle. The endoscope 2 includes an image sensor 25 in which a plurality of pixels that photoelectrically converts light from the object irradiated with the illumination light to generate and output an image signal is arranged in a matrix. The processing device 3 includes a color component calculation unit 31a that calculates each color component signal for each line of a pixel array in the image sensor 25 using output values of, among image signals output from the image sensor 25, image signals of a plurality of successive frames in accordance with the number of colors of the illumination light.
