Abstract: Based on Digital Elevation Model (DEM), land use and soil data, the Soil and Water Assessment Tool (SWAT) model for non-point source pollution in Pengxi River Basin was established. The monitoring data series of hydrology and water quality from 2009 to 2014 in sub-basins were used to calibrate the parameters and validate the model. The results show that the correlation coefficient R2 and the Nash-Sutcliffe coefficient （ENS）in calibration and validation periods are greater than 0.7 for runoff , so reliability of the model is verified. The calibrated model was used to reveal the spatial distribution of non-point source pollution characteristics for different land use in Pengxi River Basin. The results indicate that the non-point source pollution interannual distribution is uneven；the total nitrogen and total phosphorus pollution loads in 2011 were the highest from 2011 to 2014, which were 2655.17 t and 167.14 t; in general, the non-point source pollution of different land use were concentrated in the south of the basin and the low-lying area along the river; for the same watershed slope and soil type, the total nitrogen and total phosphorus pollution loads of the arable lands were the highest ,which were 1631.47 t and 146.34 t; the grasslands was the second highest contributor, and the pollution load of the woodlands was the smallest.