Architects usually use fabulous form to express their unique concepts. However, architects’ 
unique concepts oftentimes play an important role in the arrangement of structural system. The best system needs not only to convey architects’ design conception, but also to satisfy the rationality and economy of structural system. The project of CSC Headquarter Building is used in this paper to show how to integrate the different design conception between architects and structural engineers. The final structural system is decided by evaluation and integration of some alternatives during the design procedure. 
CSC Headquarter Building is a 29-floors office building (total building height is 126 m). This structure is composed of steel structure and the mega truss system is used to form the perimeter frame of entire structure. Internal frame uses the special moment resistant frame (SMRF). The columns of main building are box type steel column with Self-Compacting Concrete. The girders are made of steel as well and ductile reduced beam sections are completed in some girder to promote the capacity of plastic hinge rotation. 
This paper illustrates design conception, advantages and disadvantages of each alternative to 
decide final structural system. Structural characteristics and design results of this final scheme are also introduced. Finally, pushover analysis is also done to verify the ductility and earthquake-resistance capacity of this structure. And the design demand is confirmed as well in this structural system.