An endoscope system includes a light source unit, a band limiting unit, a light source control unit, an imaging sensor, an imaging control unit, and an oxygen saturation image generation unit. The light source unit includes a V-LED that emits violet light, a B-LED that emits blue light, a G-LED that emits green light, and an R-LED that emits red light. The band limiting unit generates measurement light having a specific wavelength band for measuring the oxygen saturation from the blue light. The light source control unit switches the control of the light source unit between a first light emission mode, in which the observation target is irradiated with the violet light, the measurement light, the green light, and the red light, and a second light emission mode, in which the observation target is irradiated with the measurement light.
