In this paper, dynamic stress response of a steel girder bridge subjected to vehicles is investigated, using field measurements and numerical simulations. The objective of this research is to investigate the capability of a FE model in predicting bridge response and extend to study stress responses in local members. Comparisons between the measurement and the simulation results were conducted in the global responses and local stress responses. The global responses are in good agreement. Furthermore, the local stress responses in the simulation are sensitive to the area setting of the contact force from the vehicle. By adjusting the contact area of tiers, the simulation obtains a satisfactory match between the simulated and measured responses within 20% difference for all local stress responses.