Based on the method of UAV photogrammetry and random vibration test， this paper explores a method to evaluate bridge conditions under non-closed traffic conditions. Using a bridge in Changsha as an example， the bridge line shape， bridge disease， and dynamic characteristics were studied by using structural identification theory and UAV oblique photography technology. The UAV 3D oblique photography technology is used to reconstruct the 3D scene model of the target bridge and to extract the bridge line shape through the point cloud model. The UAV measurement line shape is compared with the leveling line shape and the design line shape. It is found that the average value of the line shape difference is 0.034 m， the average relative deflection value is L/12705， and the standard deviation is 0.035 m. The two results are close， which verifies the reliability of the UAV measurement bridge line shape and that there is no significant change in the appearance size during the operation of the bridge. The small UAV technology was used to investigate the appearance quality of the target bridge， and the pier disease and bearing damage characteristics were investigated. The results showed that the bridge had no structural damage. Through the environmental vibration test of the structure， the Complex Modal Indicator Function （CMIF） method is used to capture the structural modal parameters （frequency， mode shape， damping ratio） with the load of driving and wind as the excitation. By comparing the historical baseline modal data 10 years ago and considering the influence of ambient temperature， it is judged that the structural stiffness of the bridge does not decrease significantly. The research shows that the comprehensive evaluation technology of bridge health status using “UAV 3D modeling linear measurement+UAV disease investigation + random vibration test” is feasible， economical， and practical.