In view of the characteristics of the beam bridge differential driving comfort, to explore the passing vehicle ride comfort, in the process of driving on the highway bridge was deduced in detail considering people - seat vibration equation of vehicle, with a beam bridge as the analysis object, based on the theory of vehicle bridge coupling vibration, further establish the interaction between vehicle and bridge coupled vibration differential equation. The seat acceleration of the vehicle was calculated by the self-programmed bridge coupling MATLAB program, and the ride comfort of the driver and passenger was evaluated according to the root mean square acceleration evaluation method in the international standard ISO2631-1. The influences of vehicle type, seat position, vehicle weight, bridge roughness, speed and many other factors on the ride comfort of the vehicle were analyzed. The results show that the driving comfort of car is better than that of truck and bus for different vehicle types. For a two-axle bus with multiple rows of seats, the ride comfort of the front seat is better than that of the back seat, and the farther the seat is from the vehicle centroid, the worse the ride comfort is. Vehicle ride comfort is very sensitive to bridge deck road condition, and it decreases rapidly with the deterioration of bridge deck road condition. Different vehicle weight, vehicle ride comfort increases with the increase of vehicle weight; Vehicle speed has a certain influence on ride comfort, but the influence is small. In order to improve ride comfort, it is suggested that speed limit measures should be adopted for driving vehicles of beam bridge.