Abstract: The pile-anchor supporting structure with its low technical requirements and wide applicability has been highly received by the design and construction units.But the current practice of geotechnical engineering remained ahead of theory,the progress of technology must put forward higher design requirements on foundation pit.Analysis of a deep foundation pit in Shunyi district by FLAC^3D,simulate the curve of soil pressure distribution.Compared with the classical soil pressure theory,the displacement of the pile,the tension of the anchor is close to the measured value.The simulate curve of soil pressure distribution accord with engineering practice more.In this paper,the research of the soil pressure distribution in silty clay is very important for optimizing the structure design and reducing the construction cost.