Building information modelling (BIM) has been adopted in the architectural heritage industry. The digital protection method with BIM Technology as the core can introduce the information management workflow into the protection of architectural heritage, which can provide possibility for the complete preservation of all kinds of information related to the architectural heritage, improve the efficiency of protection, and meet the management needs of the whole life cycle of the architectural heritage. This paper is based on digital technology and combined with the characteristics of architectural heritage to create a BIM model of architectural heritage. The Autodesk Revit software, which is commonly used in China, is used as the entry point, and the C# language is used to develop Revit to make up for the shortcomings of traditional architectural heritage protection. At the same time, all kinds of information related to the architectural heritage are completely preserved, improving the efficiency of protection work, and meeting the information management needs in the process of building heritage maintenance and management.