Taking a deep foundation pit supporting engineering in complex environment as an object, combined with engineering geological conditions and exploration test, comprehensive support schemes of “grouting micro steel pipe pile grouting micro root pile hanging net shotcrete anchor bar pre-stressed anchor cable” and “reinforced concrete row pile jet grouting pile hanging net shotcrete” are put forward, and the selection of design parameters and the construction technology are also described. The practice shows that the support scheme has good applicability and safety, which can provide reference for the design and construction of similar foundation pit engineering.