An endoscope apparatus comprising: an illumination section (11, 14) configured to radiate at least one or more illumination lights having a predetermined wavelength band to a subject; an image pickup section configured to pick up an image of a return light from the subject based on radiation of the illumination section (11, 14), and generating an image signal; a band decomposition processing section (101, 104) configured to receive the image signal from the image pickup section and perform processing for decomposition into multiple spatial frequency bands, with respect to a first image signal corresponding to a first wavelength band having a narrowband spectral characteristic, the first wavelength band having a center wavelength between 580 nm and 620 nm; an emphasis processing section (101, 101a) configured to generate a signal obtained by performing emphasis correction for luminance adjustment for a band image signal with a lowest spatial frequency among multiple band image signals obtained by the decomposition processing by the band decomposition processing section (101, 104); a color conversion processing section (101, 101b) configured to perform processing for respectively giving predetermined coefficients to the signal emphasis-corrected in the emphasis processing section (101, 101a), a second image signal and a third image signal, and allocate the image signals to color channels of BGR, the second image signal corresponding to a second wavelength band having an absorption coefficient of the hemoglobin absorption characteristic lower than an absorption coefficient of the hemoglobin absorption characteristic of the signal corresponding to the first wavelength band and having such a spectral characteristic that a scattering characteristic of the living tissue is suppressed, the third image signal corresponding to a third wavelength band having a narrowband spectral characteristic, the third wavelength band having a center wavelength of 415 nm, 460 nm or 540 nm; and a display section configured to display the signals allocated by the color conversion processing section (101, 101b). an illumination section (11, 14) configured to radiate at least one or more illumination lights having a predetermined wavelength band to a subject; an image pickup section configured to pick up an image of a return light from the subject based on radiation of the illumination section (11, 14), and generating an image signal; a band decomposition processing section (101, 104) configured to receive the image signal from the image pickup section and perform processing for decomposition into multiple spatial frequency bands, with respect to a first image signal corresponding to a first wavelength band having a narrowband spectral characteristic, the first wavelength band having a center wavelength between 580 nm and 620 nm; an emphasis processing section (101, 101a) configured to generate a signal obtained by performing emphasis correction for luminance adjustment for a band image signal with a lowest spatial frequency among multiple band image signals obtained by the decomposition processing by the band decomposition processing section (101, 104); a color conversion processing section (101, 101b) configured to perform processing for respectively giving predetermined coefficients to the signal emphasis-corrected in the emphasis processing section (101, 101a), a second image signal and a third image signal, and allocate the image signals to color channels of BGR, the second image signal corresponding to a second wavelength band having an absorption coefficient of the hemoglobin absorption characteristic lower than an absorption coefficient of the hemoglobin absorption characteristic of the signal corresponding to the first wavelength band and having such a spectral characteristic that a scattering characteristic of the living tissue is suppressed, the third image signal corresponding to a third wavelength band having a narrowband spectral characteristic, the third wavelength band having a center wavelength of 415 nm, 460 nm or 540 nm; and a display section configured to display the signals allocated by the color conversion processing section (101, 101b).