Abstract: Composite foundation settlement of an office building in Chinese Hangzhou development region was numerically simulated with FLAC software, According to engineering practice, displacement vector and settlement analyses on the simulated results were carried out, and the calculated settlements were compared with the measured ones. On the basis of the research on the numerical simulation results and measured settlement data, main factors influencing CFG pile composite foundation settlement were summarized. It is found that composite foundation settlement was obviously affected by pile-soil interaction, pile setting, load-to-time relation and soil stress distribution.