Compared with the virtual reality (VR) technology and augmented reality (AR) technology, the mixed reality (MR) technology owns the advantages of flexibility, interactivity and real-time performance. Therefore, the MR technology has gradually become an important way to realize intelligence and informationization in different industries. The application of building information model (BIM) technology has promoted the informatization of the construction industry, while the combination of MR + BIM becomes a new research direction in our construction industry. Through using the Hololens developed by Microsoft, this paper explores the application of BIM technology in construction, which is able to enhance the visualization, real-time and high-efficiency construction industry, which provide new ideas and new methods for building engineering intelligent and informatization.