Abstract: In order to deal with the problem of heterogeneous distribution of vehicle terminals in heterogeneous IoV(Internet of Vehicles), which leads to the high switching failure rate and the decrease of network throughput, a vertical switching algorithm based on fuzzy analytic hierarchy process(FAHP) is proposed in this paper. Firstly, through predicting the switching time for the candidate network load state, the vertical switching algorithm to select adaptive network. And then use FAHP to determine the weight of each attribute. Finally, make use of technique for order preference by similarity to ideal solution (TOPSIS)algorithm to decide the optimal target network. The simulation results show that the proposed algorithm can reduce the switching failure rate, reduce the switching delay and improve the network throughput of the system under different vehicle terminal scenarios.