In this study, we suggested 4 plans to reduce non-point pollutant sources in Dongcheon and analyzed their controlling effects by water quality modeling, XP-SWMM. To do this we identified the influx of non-point pollutant sources to the initial rainwater through the water quality survey in the river and analyzed the causes of them at major locations, and suggested 4 kinds of plans reducing non-point pollutant sources. Plans reducing the non-point pollutant sources through cleaning the industrial road around the river(plan A), through a separate treatment facilities like the gutter(plan B), through installing treatement facilities(plan C), or through combing plan B and C(plan D) were analyzed using XP-SWMM model. The analysis showed that plan A, B, C and D reduced non-point pollutant sources average 21.7 %, 24.7 %, 49.3 %, 56.7 % respectively. Therefore, the water quality pollution in Dongcheon due to the influx of non-point pollutant sources is considered to be reduced effectively though cleaning the road, installed at the exits of paddy or factory basins, invasion type facilities or equipment-type facilities.