Abstract: Based on an analysis to the factors of affecting real-time performance,the robustness,and matching precision of the map matching algorithm,according to the continuity of the vehicle movement,the idea of partitioning the road net into certain grids is introduced.Meanwhile,using the information about the position and the direction of the vehicle running,and the topological feature of the road network,a novel map matching algorithm,with its time complexity of O（c）,is proposed in this paper.The simulation results aimed at the practical running data show that the correct rate of the new algorithm is no less than 95％,and the matching time for the individual positioning point is less than 0.01ms.