On the bases of information from archaeological excavations (in 1959-1960 and 1995-1996) , the author prosposes a restoration of Tang Dynasty Han-yuan-dien, Da-ming-gong. The restoration has modified the absence of the restoration in 1960's. The representation in terms of architectural history provides us more fundational and academic knowledge on the understanding of the architectural form of the empire, and the symbol of Chang-an city in Tang Dynasty.