An apparatus and a method for detecting damage to a linear guide on which a robot is mounted, by using a simple configuration. The apparatus has: a length measuring sensor configured to measure a position of a predetermined portion of the robot at predetermined time intervals; a current detecting section configured to detect a current value of a drive motor for driving a slide; and a judging section such as a processor, configured to, when the measured distance between the predetermined portion of the robot and the length measuring sensor is out of a range defined by a predetermined first threshold, and when the current value of the drive motor is equal to or higher than a predetermined second threshold, judge that the linear guide has been damaged.