The soil layer in Kunming is mostly formed by the deposition of ancient Dianchi, thick silt soil exists in the underground. The pile anchor structure is commonly used for foundation pit retaining in this area. The innovative application of double-row piles retaining was carried out in a project with good effects. According to this project construction, the paper analyzes the retaining characteristics, calculation model and construction effect, summarizes the technical experience and puts forward the improvement suggestions to double-row piles retaining in silt soft soil layer.