Abstract: Borehole cast-in-place concrete pile cantilever retaining structure and single-pivot mixed retaining structure are usually deep-foundation retaining structures．Borehole cast-in-place concrete pile multi-arch retaining structure is a new retaining structure．Based on the in situ measured data and discussion on pile body stress at certain deep-foundation pit excavation in Nanjing city，the magnitudes and distribution patterns of force acted on single retaining pile at different excavation depths in different retaining structures under same engineering geological and hydrogeological conditions，but in the same conditions of construction and cut down groundwater were obtained．Valuable information is provided in this paper for retaining structure design of pit excavation and extending use of borehole cast-in-place concrete pile multi-arch retaining structure．