Abstract: It is required to guide drivers to divert to the alternative route when non-recurring congestion happens in the network, as well as to controll the traffic in the congested route. Delay time and queuing length, which are information of reflecting the congestion degree, are predicted by using the deterministic queuing method in this paper. The arrival rate of vehicles decides the magnitude of traffic controlled, so the control objective is designed as the arrival rate of vehicles less than the route capacity when incident happens. A fuzzy logic reasoning algorithm is designed to control the traffic in the congested route, and a simulation analysis is also given in this paper. The analysis results indicate that this fuzzy reasoning algorithm, to some extent, can replace traffic engineers' management work and improve the efficiency of congestion management.