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Fractal theory was used as one of the methods to quantitatively analyze soil particle size distribution (PSD) because it can better describe soil physical properties. The single- and multi- fractal were used to analyze the features of the soil PSD, the effects of different land use types on fractal parameters and the relationship between fractal parameters and soil PSD. Results showed that soil PSD was diversity in different regions of the Loess Plateau. Soil particle size, which was measured by laser method, was mainly distributed in two power-law domains, named Dsilt and Dsand. It was needed to redefine the domain boundary of Dclay, Dsilt and Dsand. Soil particle size was distributed in range of 20~100μm which was narrow and presented obvious heterogeneity, thus it was necessary to use multi-fractal method to describe soil particle distribution characteristics. The correlation analysis indicated that Dsilt showed prominent positive correlation with content of clay and silt (P＜0.01), Dsand showed negative correlation with sand content but not prominent. Consequently, Dsilt can be used to predict the change of soil texture and soil erosion degree of different land use types. There was an extremely remarkable effect of land use types on clay, silt, sand content, Dsilt, D0, D1 and D1/D0 value (P＜0.01), and remarkable effect on Dsand (P＜0.05), which indicated that multi-fractal parameters can be the indexes to reflect effects on soil properties.