For non-uniform continuous bridge in actual projects, the theoretical analysis and field testing of the dynamic response under moving vehicle are carried out. Firstly, Euler-Lagrange equation is applied to derive the vibration equation of three-axle vehicle. Then one obtains the dynamic analysis model by using the finite element method and the vehicle-bridge interaction equation based on the displacement coordination relationship of the contact between wheels and bridge. Lastly, numerical solutions are presented according to the dynamic response of the bridge, compared with the real values. The results show that: the roadway roughness and vehicle speed strongly influence the impact factor.