In a mobile robot and a method for measuring a moving distance thereof, by including an image capture unit for photographing the bottom surface according to motion of a mobile robot at a certain intervals and capturing images; a displacement measurer for measuring displacement about the captured image; and a microcomputer for outputting an actual moving distance by direction and motion of the mobile robot on the basis of the measured displacement value, it is possible to measure an accurate moving distance of the mobile robot with only one image sensor installed at the center of a body of the mobile robot, and accordingly it is possible to simplify a mechanical structure and facilitate maintenance and repairing.