With the rapid development of urbanization, urban land has been expropriated and developed on a large scale. Moreover, people’s awareness of the protection of historical buildings is relatively weak, so some historical buildings have been demolished or rebuilt. Historical buildings have played an important role in the spread of national culture, so how to use some methods to protect historical buildings from being destroyed has become an urgent problem to be solved. The protection of historical buildings includes a series of complicated and rigorous procedures, such as on-site drawing and mapping, survey and design, and scheme discussion and construction. The surveying and mapping of traditional historical buildings require people to do it by themselves, so it is inevitably time-consuming and labor-intensive. This paper first discussed and analyzed the significance of historical building protection, and then used digital technology to make up for the shortcomings of traditional manual surveying and mapping and historical building protection methods. Modern technologies such as three-dimensional laser scanning technology and virtual reality technology are used to restore the style and appearance of historical buildings. Among them, in terms of the color of historical buildings, the restoration degree of buildings based on digital protection technology has reached 56.1%; at the same time, the efficiency of information collection and processing, and virtual model construction has also been improved. Thus, the ultimate goal of historical building protection is achieved, and it provides a reference for the digital protection of historical buildings.