With the rapid advancement of technology, accurate and reliable architectural heritage information is increasingly in demand in the fields of cultural heritage and architectural conservation. This study aimed to establish a positive and harmonious relationship between architectural heritage and urban renewal in China’s sustainable urbanization process by documenting and conserving Chinese architectural heritage information. This work focuses on integrating architectural heritage information into multilevel and multi-dimensional information using scientific and standardized classification methods for documenting and conserving Chinese architectural heritage. The former site of the provisional Senate of the Nanjing National Government was studied and documented for this purpose. A precise 3D modeling for the components of architectural heritage and building information modeling (BIM) technology based on the two-dimensional (2D) drawings and component information were studied, analyzed, and used for restoration. Finally, a component “family” library was created using the common components of existing historical buildings. The results showed that the proposed method could provide both 3D and 2D drawings directly in the digital protection of historical buildings to monitor, repair, and protect architectural heritage, particularly historical buildings, throughout their life cycle. Overall, this work highlights the importance of protecting architectural heritage in sustainable urbanization and proposes an effective method for achieving this goal.