As a key foundation work for nuclear power plant construction, construction setting out is the basis for other construction activities, which has a direct impact on the quality and progress of the project. At present, the construction setting-out method of point-by-point setting-out with total station is mainly used in the field of nuclear power construction and installation, which has the disadvantages of poor setting-out accuracy, low construction efficiency and large investment in labor costs. In this paper, the application of 3D laser projection technology is put forward to realize the rapid construction lofting of nuclear power plants, which has the characteristics of batch lofting and high projection accuracy. Through the feasibility analysis of construction lofting of nuclear power plants and the on-site application of a nuclear power project, as well as the use of total station for comparative analysis, it is verified that 3D laser projection technology has a certain application prospect in the construction lofting of nuclear power plants.