A control apparatus controls a bio-optical measurement apparatus which is configured to be inserted into a subject through an endoscopic device and is configured to perform an optical measurement of a biological tissue in the subject. The endoscopic device is configured to capture, by inserting a distal end part of the endoscopic device into the subject, in-vivo images of the subject by an imaging unit provided at the distal end part. The control apparatus includes a position determining unit configured to determine a position of the distal end part in the subject, and a permission signal outputting unit configured to output a permission signal for permitting the bio-optical measurement apparatus to perform the optical measurement based on a determination result by the position determining unit.