The relationship between soil fractal dimension and soil properties under five vegetation types (Quercus aquifolioides，Abies taxoniana，Sinarundinaria fangiana，board leaved forest and subalpine meadow) in upper reaches of Minjiang River was studied based on data of the soil particle composition and fractal theory． The fractal dimension of surface soil particle size distributions of the fifteen plots ranged from 1． 117 to 1． 315． This fractal dimension only had a significant correlation with the content of ＜ 0． 002 mm soil particles by stepwise multivariate regression． The infiltration process was divided into three phases according to the soil infiltration process curve: (1) the initial phase(0 ～8 min); (2) the transition phase(8 ～ 30 min); (3) the stable phase(30 ～ 120 min)． Soil infiltration process was influenced comprehensively by soil partical size distribution(PSD)，aggregate size distribution(ASD) and soil pore size distribution(SPD)． During the process of soil water infiltration，the infiltration rate of Quercus aquifolioides，Sinarundinaria fangiana and board leaved forest was faster than that of Abies taxoniana and subalpine meadow．