According to the characteristics of construction of deep foundation pit in Shanghai, combined with the practice of Shanghai Zhongshan Hospital Comprehensive Building, the following technical measures were used, such as the ventilation lighting technology, borrow mouth set technology, the construction technology of underground continuous wall, a column and a pile verticality control technology, a hierarchical underwater concrete perfusion technology, large open partition hidden digging technology etc.The monitoring results showed that a variety of deformations could meet the relevant code requirements, which effectively controlled the deformation of foundation pit, thus protecting the surrounding environment and safety of buildings, solved the key technology of top-down construction of a large irregular deep foundation pit, good economic and environmental benefits were obtained.