In order to solve the problem of designing the specific paths for the air-rail network, according to the research method for the p-hub median problem of hub and spoke network, a mixed integer programming model is established, direct flight is permitted in this model, with the minimum total transportation cost as the objective function. The model is solved using the shortest path algorithm which is based on traversal and search method. Finally, sample cities are selected to be applied to the model and its algorithm. The optimized objective value and specific paths are calculated with different variable parameters, and the air-rail network of China's fourteen cities is constructed. The result shows the close relationship among the minimum total transportation cost, the number of specific paths, number of hubs-m and the discount factor-rho. The bigger the value of m and the smaller the value of rho, then the smaller total transportation cost and the more specific paths; vice versa.