Disclosed are a robot, which builds a map using a surface data of a three-dimensional image, from which a dynamic obstacle is removed, and a method of building a map for the robot. The method includes sequentially acquiring first and second surface data of a route on which the robot moves; matching the first and second surface data with each other to calculate a difference between the first and second surface data; detecting a dynamic obstacle from the first and second surface data according to the difference between the first and second surface data; generating a third surface data by removing the dynamic obstacle from at least one of the first and second surface data; and matching the third surface data and any one of the first and second surface data with each other to build the map.