The spatio-temporal variation of non-point source pollutants in Lake Wuli has been studied through analysing production process of non-point source pollutants. The results show that: (1) the concentration of pollutants reached a peak immediately for the continuous rainfall, and then reduced gradually along with the time. At the begin of rainfall limiting factor for pollutant concentration in runoff water is splash erosion force, while it changed to pollution amount on underlying surface during the mid-late period. (2)The curve of the pollutant concentration seemed serrate for the intermittent rainfall because this kind of rainfall generally last for a long time, during which there are accumulated new pollutant in some drainage basins. (3)The monthly variation curve of pollutants concentration seemed serrate, influenced by accumulation and attenuation of the pollutants, former rainfall, and the intensity of the rainfall, et al. (4) The spatial variation of pollutants was influenced by the characteristics of the ground, sources of Pollutant, pollutant degree, et al.
