The main cost and decoration cost of the building are the key parameters in the evaluation of the direct economic loss of the building. In the Earthquake Site Work Part 4 : Direct Loss Assessment of Disasters ( GB / T 18208.4-2011 ), considering factors such as economic development level, structural type, and building use, based on expert experience and engineering cost data, a grading index was developed and a corresponding correction coefficient was given to more accurately and reasonably assess the loss of the main building and the loss of decoration. In view of the rapid development of China 's economy and the acceleration of urbanization in the past ten years, the original grading indicators and coefficients need to be adjusted to adapt to the reality. This paper focuses on the reinforced concrete structure with various functions and wide distribution. By collecting a large number of corresponding building main body and decoration cost data, and combining with expert experience data, this paper analyzes the influence of seismic fortification level on the main body cost, as well as the influence of economic development level, decoration grade, use function and other factors on the decoration cost. The research results of this paper aim to provide reference for the update and refinement of several key parameters in the specification.