Provided is a medical image processing system that can stably control the light emission amount of narrow-band light of a short wavelength in a case where the narrow-band light of the short wavelength is used for illumination of an observation target. A light source circuit emits specific narrow-band light of a short wavelength. An image sensor includes a first pixel group including a B pixel and a second pixel group including a G pixel. The B pixel has a higher sensitivity to the specific narrow-band light than the G pixel. The G pixel has a sensitivity to light in a green band and the specific narrow-band light. The light source control unit controls the light emission amount of the specific narrow-band light on the basis of a pixel value of the B pixel and a pixel value of the G pixel.