Route guidance can effectively solve the increasingly crowded urban traffic problem. In this paper, a research on multi objective path guidance based on increment searching was presented. Firstly, the graph theory method was used to abstract complex road networks to weighted graph that consists of points and lines. Then, a road network model was established by introducing multi objective optimization variables. Secondly, a heuristic search algorithm based on incremental searching was proposed to achieve vehicle dynamic route guidance. This algorithm combines with the global planning and local dynamic re planning. Finally, simulation results show that this method can effectively solve the vehicle real time dynamic route guidance problem in complex road networks.