With the rapid development of construction industry in China, the applications of steel structure in construction industry also continues to expand. The finished product inspection & test of complex steel components has become a bottleneck in engineering technology. Combining with the information technology pre-assembly of the third ring steel truss components in Shanghai Center Tower project, this thesis describes the advantages of Integrated utilization of three-dimensional modeling software in complex space bar lofting and the features of precision measurement of space coordinates by using total station instrument. It effectively solve the complex problem of inspection & test of steel components and improve fabrication precision of complex steel components to ensure smooth erection at site.