Stationary soil-moisture-observation was carried out in Xiuwen County, Guizhou Province, which lies in the karst mountainous area of Southwest China.Based on the two year observation from June 13, 2001 to July 23, 2003, impacts of gradient and land use on soil moisture are analyzed systemically.The result shows that gradient and land use have a marked effect on soil moisture.Comparison of change in soil moisture between soils under three different kinds of land uses shows that it is the most remarkable in soil under vegetable, and there is no significant difference between bared soil and soil under wheat or corn.But in terms of effect of slope on soil moisture, surface runoff shows a decreasing order of 16°>9.5°>6.5° in gradient field while soil moisture has a decreasing order of 9.5°>16°>6.5° in gradient field.According to a preliminary analysis, the difference in soil profile structure is the potential cause.Soil profile soil moisture increases with the depth in the soil profile.In conclusion, the impact of gradient and land use on soil moisture is mostly effect ive in the soil layers above the BC layer, and is quite weak in the C layer.And the impact of gradient on moisture distribution in depth is lower than that of land use.