Method and apparatus for localization in mobile robot

A method and an apparatus for presuming location/direction of a mobile robot in dark or severely changed lighting environment are provided to solve a kidnapping problem of the robot by making the robot presume the location/direction in real-time through a small-noise image process, and simplify the image process for detecting marks by installing the artificial marks on a ceiling and detecting it with a pattern recognition method. A ceiling image obtainer(210) obtains a ceiling image of a place driving the mobile robot. A brightness comparator(220) determines whether the current environment is bright or dark by calculating an average brightness of the ceiling image and comparing it with a reference. A lighting controller(270) controls a lighting device attached on the robot depending on a judging result. A mark detector(240) detects the artificial marks comprising the first and the second mark formed with a non-reflection part and an infrared reflection part. A location/direction presuming part(260) presumes the location/direction of the robot by using location or encoder information of the artificial mark according to an artificial mark detecting result. A driving controller controls drive of the robot depending on the presumed location/direction.