Abstract: A robot for surgical operation which comprises arm structure mounted at its one end of a vertical support and extending in a predetermined direction.The robot comprises a drive mechanism mounted on the other end of the arm structure and adapted to extend substantially horizontally further in said predetermined direction. A head or trepan is mounted at the extended end of and driven by said drive mechanism. Light transmissive fiber or the like mounted on the trepan takes an image of the patient and a controller process the image through video data processing for driving the arm structure, thereby controlling the position and tilt of the trepan with respect to the patient.