Abstract: This paper designed the optimal routing algorithm for vehicular networks and simulated it based on the two-year GPS data of 4 000 taxis in Shanghai.The optimal algorithm,on the one hand,revealed the inefficiency of existing routing algorithms.And on the other hand,its actual routing traces suggested a map-based static structured routing strategy with dynamic weights.Simulations showed that the performance of this new practical routing strategy,compared with other existing routing algorithms,has an improvement of 50%.