If a wireless resource congestion occurs, the wireless resources of the entire system are used efficiently to reduce a disconnection of communication with a congested sector and a state in which a new call cannot be originated nor terminated. A base station control apparatus compares the wireless resource usage amount of each sector of each base station with values stored in a wireless resource threshold table. If a sector of a base station is in the light congestion state, the neighbor search window size of a sector specifying the congested sector as a neighbor is changed to restrict a soft hand-over to the congested sector. If a sector of a base station is in the heavy congestion state, a mobile station which is communicating in the congested sector and receiving radio waves of another sector with stability is subjected to a forced soft hand-over.