Abstract: An apparatus and method for allocations segments in a broadband wireless communication system is provided. Sector pairs are generated with respect to all sectors existing in different cells and the generated sector pairs are sorted according to priority based on a proximity. A sector pair having a top priority among unselected sector pairs is selected. Segments are allocated to all sectors of a cell including each sector of the selected sector pair. Accordingly, segments can be allocated to sectors while minimizing downlink throughput deterioration caused by segment duplication.