We studied infiltration and fractal mechanisms on sloping farmlands in a small watershed in Shandong Pro-vince in the rocky mountain areas of north China. We studied soil fraction and soil water retention curves, and developed a soil infiltration model to analyze its quantitative relationship with soil particle size and pore dimensions under four types of land use, including sloping farmland, aban-doned land, natural forest, and forest plantation (Malus pumila, Crataegus pinnatifida). Soil stability infiltration rate ranked as sloping farmland>abandoned land>natural forest>forest plantation. The sequence of soil particle size and pore dimension ranked as natural forest>forest plan-tation>abandoned land>sloping farmland. There were significant positive correlations between soil particle size and pore dimension, and both were positively correlated with the percent volume of silt and clay. They were negatively correlated with soil infiltration rate. The Horton model and the power function model were more suitable for simulating soil infiltration and the infiltration rate. We concluded that the soil in this area displayed typical fragments of rocky mountainous regions due to the loss of silt and clay caused by cultivation on sloping farmland. The uniformity and fractal dimensions of soil particle sizes and pore distribution decreased, thereby enhancing soil infiltration capacity and decreasing soil water retention capacity.