1. A method to build a map for a moving robot, the method comprising: acquiring, by a computer, 3D distance information of an object present in a path along which the moving robot moves; and by at least one computer: accumulating, by the computer, the acquired 3D distance information to construct maps, each constituted by three-dimensional (3D) cloud data, of a specific size level and storing the maps in a database; hierarchically matching, by the computer, the maps stored in the database based on the size levels of the maps to build a 3D map for a set space; and controlling, by the computer, the moving robot in accordance with the built 3D map.