Reflecting the mechanical parameters of rock mass accurately is an important problem in solving rock mechanical problems. In particular, it is very important to analyze surface subsidence characteristics due to mining space, to ensure stability of surface and underground facilities and structures due to underground mining, and to reduce ore losses due to protective pillars. Concerning the surface subsidence characteristics, it is also important to measure and reflect the mining space more accurately, since this depends on the size and shape of the mining space. In this work, we applied a new method to input the mechanical parameters per element, and then built the FLAC3D analytical model from those elements, which leads to a more realistic analytical result. The proposed method was applied to the analysis of the surface subsidence characteristics due to the mining site of the Yongsan mine in the Chongsong region. During this process, the mining space was measured and modeled using a laser mining space measurement system, a solid model was built using Surpac software, the mechanical parameters of the elements were estimated, and more than 500,000 elements were imported into FLAC3D for analysis.