Abstract: For the excavation for large and deep foundation pits under complex environment, on the premise of meeting the safety and environmental protection requirements, the combination design of supporting structures is more reasonable and effective. Based on the first stage project of integrated transformation of Hong-Cheng square in Guangzhou, the design method of “Combined anchoring and retaining, overall to-down excavation and bottom-up excavation” is analyzed. In the overall design, through reasonable plane and space combination a variety of supporting structures play a great role in security, rationality, economy of excavation engineering. It is worthy of reference in similar projects.