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Totally 4 farm roads, i.e. the bare unpaved road, the stone covered road, the stone and grass covered road and the grass covered road, were selected on the representative area named Jiangxi Eco-science Park of Soil and Water Conservation. Twelve rainfall simulation experiments with an intensity of 3.0mm/min were carried out on the selected roads. The results indicated that runoff from the farm roads was recorded less than 2min. The runoff rate increased quickly and reached steady level in the first 2~6min. The runoff coefficient was above 65%. The erosion rate was high at the beginning of the rainfall and then decreased due to the loss of fine soil surface particles and porosity changes. At later period, the erosion rate of the bare unpaved road increased to some extent due to the appearance of rill and micro-gully. Compared with the bare unpaved road, the stone covered road, the stone and grass covered road and the grass covered road can all change the runoff hydraulic characteristics, so to protect the farm roads and decrease sediment yield. The lowest benefit of sediment reduction was up to about 40% among them, and the grassed road had the best benefit of soil and water conservation.