Since regional bridges are widely distributed and large in quantity, it is difficult to comprehensively evaluate them. This paper establishes a condition assessment theory for regional bridges based on the integrated multi-source information of single bridge. The database of regional bridges is stored within a “route-bridge-component” formation, which is extracted from inspection reports, monitoring systems, traffic data, design drawings, and so on. Based on the integrated multi-source information of regional bridges, the performance evaluation of the regional bridges and network-level assessment can be carried out. Taking a partial highway in Hebei province as an example, three sub-regions were divided according to climate characteristics, and the overall and regional characteristics of the road network were evaluated. Data mining was carried out concerning key parameters such as bridge type, age, and traffic volume, and correlation analysis was conducted between these parameters and general technical scoring at network level. The proposed framework provided data basis and analysis conditions for network-level evaluation. Results indicate that the proposed data integration and mining methods can effectively reveal the common features and deterioration rules of regional bridges, and hence can be used for network-level assessment of regional bridges.