Abstract: Pore structure characteristics directly affect the permeability,deformation,and strength properties of soils. Quantitative analysis of pore structure characteristics of soils has always been a difficult problem in soil mechanics. Pore structure characteristics of cement-stabilized soils are used to explain the reinforcement mechanism. The total pore volume and pore distribution of different pore diameters of cement-stabilized soil are measured quantitatively through the mercury injection experiment in this paper. The effects of cement content,age,moisture content,and dry density on the median and average pore diameters of cement-stabilized soil are analyzed,and the reinforcement mechanism of cement-stabilized soil is revealed. Based on the mercury intrusion test results of cement-stabilized soil,a fractal model of pore distribution of cement-stabilized soil is established. The relationship between the fractal dimension of the pore-size distribution and the cement content,age,moisture content,and dry density of cement-stabilized soil is analyzed.