The efficient functioning of complex networks rely on their traffic capacity, so it is significant to improve their throughput. We propose a new efficient routing strategy called weighted routing strategy to enhance the traffic capacity. Each edge is assigned a value that is related with its end degree. Then packets are transported across the shortest paths of the weighted network. This kind of paths can more evenly go through the vertices and utilize their transport ability. They avoid collectively passing certain vertices which makes them congested, thus the throughput of the network is improved. It is demonstrated by simulations that our strategy is more powerful than the traditional shortest-path strategy, and improves tens of times the throughput for many structures of networks.