Using numerical analysis and comparison of three types of composite foundations used to treat liquefied saturated silt, a summary of the anti-liquefaction performance of the three types of composite foundation was determined. The experimental results showed that:(1) the development trend of excess pore pressure of natural saturated silt was the same at different depths, but the pore pressure of the shallow layer is lower. The distribution of the pore pressure ratio is small in the shallow layer and high in the middle and deep layers.(2) In terms of reducing the pore pressure, the multi-pile(gravel pile + cement, fly-ash gravel(CFG) pile) composite foundation and the gravel pile, both have little effect on the pore pressure of the shallow and middle layers, but the gravel pile has better effects on the deep layer.(3) In terms of reducing vertical deformation, multi-pile(gravel pile + CFG pile) and CFG pile are more effective than the gravel pile, but the multi-pile foundation offers the most pronounced effect.