Taking urban express traffic as an example, this paper lists two optimization improvements of Dijkstra algorithm. One is to improve the calculation method of the algorithm to make the calculation more directional, so as to reduce the total amount of calculation. One is in the form of a graphical model, reducing the number of nodes to optimize the calculation process. By comparing the calculation results with the complexity of the traditional algorithm, the effectiveness of the improved method is proved, the complexity of the algorithm is reduced, and the actual work efficiency is improved. It improves the application ability and realizability of Dijkstra algorithm in practical problems.