A light source device for an electronic endoscope includes a light source that emits light having a visible light wavelength region and an optical filter that has transmission peaks at a plurality of particular wavelengths in a continuous wavelength region including the visible light wavelength region. The plurality of particular wavelengths include wavelengths of around 420 nm, around 550 nm and around 650 nm. The optical filter has a constant transmissivity higher than zero and lower than a half of each of the transmission peaks in a wavelength region between the transmission peaks and the constant transmissivity in the wavelength region between the transmission peaks is higher than a transmissivity in a wavelength region other than between the transmission peaks.
