An endoscope system includes an endoscopic device 2 configured to capture, by inserting a distal end part 211 of the endoscopic device into a subject, in-vivo images of the subject by an imaging unit provided at the distal end part 211, and a bio-optical measurement apparatus 3 that is configured to be inserted into the subject through the endoscopic device 2 and is configured to perform an optical measurement of a biological tissue in the subject. The system includes an external input unit 328 configured to output a permission signal for permitting the optical measurement, to the bio-optical measurement apparatus 3, and a driving controller 327b configured to control driving of the bio-optical measurement apparatus 3 when the external input unit 328 receives an input of the permission signal.
