Abstract: The article describes the design theory method, design points, and design process of the prefabricated steel frame structure, then analyzes engineering application and economic benefits of prefabricated steel frame structure.it is concluded that the design theory method of prefabricated steel frame structure has strong direction, operability and practical guiding significance, and prefabricated steel frame structure layout is more flexible, the construction period is shorter, the construction quality is better, it is more in line with the requirements of "green building, energy saving and environmental protection",and the comprehensive benefit is better.