For a flexible and inexpensive large-scale access network to the Internet, we have studied the wireless mesh network composed of access points (APs) as wireless routers. Each AP has multihop wireless connections with the others by the wireless distribution system (WDS). In this network, communications around Internet gateways are usually very crowded and become the bottleneck of performance, because most traffic go through there for access to the Internet. To avoid this problem, the proper channel configurations of APs concerning multiple network interface cards (NICs) and their channel assignments are essential, where for the given network and traffics, the throughput should be maximized while the cost for channel configurations be minimized. In this paper, we formulate this channel configuration problem for AP communications in the wireless mesh network, and present its two-stage heuristic algorithm. The effectiveness of our approach is verified through extensive simulations.