The paper selected the daily meteorology data of Baoshan station and the runoff data above dam of reservoir in Beimiao water source, and combined with land use, soil data, and DEM data to construct SWAT model so as to simulate and study the impact of land use change on hydrologic factors. The result showed that in period of calibration and validation, the value of R2 is 0.70 and 0.72 respectively.All of the simulation efficiency (Ens) value are greater than 0.55. the relative error (Re) between simulation value and observation value is less than 15%.SWAT hydrological model has better applicability in Beimiao water source.The main types of land-use are forest land, cultivated land and grass land during the period of 1986 to 2009.The main characteristics of land use variation in Beimiao water source were the decrease of grass land area and the increase of cultivated land, non-use of land and residential land.The major change of hydrologic factors mainly presented the increase of runoff depth of slope surface, runoff depth and soil erosion modulus and the decrease of actual evapotranspiration.