When the fiber optic lines of power system are repaired, transformed or destroyed by some emergencies, communication businesses will be suspended. Based on the rest of undamaged network, quickly reconstructing one circuitous path can keep communication businesses of wide area network working. The optimal circuitous path whose delay is shortest and traffic is balanced is searched in this paper. The effect that transferred data caused on the queuing time of alternative channel is considered emphatically. The sum of each channel’s bandwidth reciprocal value, length and utilization rate is considered as weighted index of channel. The path’s minimum weighted value is the optimal target. The improved Dijkstra algorithm is performed to get the optimal circuitous path in the useful circuitous path chart. Finally, OPNET is used to test the instantaneity and traffic’s balance of the chosen optimal path. This work is supported by National Natural Science Foundation of China (No. 51477090) and State Key Laboratory of Advanced Electromagnetic Engineering and Technology (HUST) Open Foundation Projects (No. 2016KF003).