An endoscope system comprises first and second emitters, a fiber, and a controller. The first emitter emits illumination light to a photographic subject. The second emitter emits infrared light. Emission intensity of the second emitter is stronger than that of the first emitter. The fiber has a tip which moves in a spiral when viewed from the photographic subject during scan periods. The controller controls emission timing of the first and second emitters. Light emitted by the first and second emitters is cast from the tip of the fiber onto the photographic subject. The second emitter emits in a predetermined period of one of the scan periods, based on control of the emission timing, so as to shine infrared light with the second emitter to at least one part of the photographic subject, in order to perform marking.