Abstract: The underground space project of Chen Clan Academy Cultural Square adjacent to world cultural heritage and urban rail transit lines is characterized by large excavation face, complex geological conditions and limited construction period. Based on the design and construction principles of safety, feasibility and rationality, different support structures for foundation pit are analyzed and compared. The top-down construction method featured with spun digging pile-lining wall interaction and basement floor system working as the horizontal interior bracing is elaborately designed. Through discussing uncertainties of the foundation pit, the reliability index on the basis of deformation of support structures is established, and the failure probability of support structures is calculated by Monte-Carlo FEM. The project is carried out safely and on schedule, satisfying the requirements put forward with the purpose of ensuring the 2010 Asian Games successfully held. It is indicated that pile-wall interaction with adverse construction as well as the relevant design parameters is reasonable and adequate to the support structures for the foundation pit of Chen Clan Academy Cultural Square.