There are a number of recreational facilities and large scale cattle farms around upper region of Song Stream, and they have raised concerns about the possible pollution of the stream. This study evaluated the extent of pollution at two segments of the stream to provide water quality data for efficient pollution source control. Stream flows and water qualities for three other small streams that flow into the segment No.3 of the Song Stream were also analysed, and these data were used to estimate pollution loadings from each stream. The estimated production pollution loading to the Song Stream were 3,079㎏ for BOD, 1,691㎏ for total nitrogen, and 176㎏ for total phosphorus. Of the total loadings, wastes from the cattle farms accounted for 79.8% for BOD, 50.8% for T-N, and 89.1% for T-P.