An endoscope apparatus includes a color image pickup device, a light source device configured to simultaneously illuminate the subject with light in a first wavelength band having a spectral characteristic of a narrow band having a peak in a range from a wavelength of 585 nm to a wavelength of 615 nm and light in a second wavelength band having a spectral characteristic for making, among a red signal, a green signal, and a blue signal, a pixel value of the red signal smallest, and a processor configured to assign either one of the red signal generated by return light from the subject illuminated with the light in the first wavelength band and the green signal or the blue signal generated by return light from the subject illuminated with the light in the second wavelength band to each of output channels corresponding to the respective colors in a display device.