This study is carried out to investigate the water quality changes in Busan Metropolitan streams, The results are as follows. The level of organic contaminants($BOD_{5}$ and $COD_{Mn}$) is found to be low and does not show seasonal variation in domestic waste water streams. But, the level of organic contaminants in industrial waste water streams is relatively high and seems to be seasonally variable, which is affected by other factors. The nutrient materials, such as nitrogen(as T-N, about 20mg/L) and phosphorus(as T-P about 2.0mg/L), are abundant than Nak Dong River and the general trends of contaminants level are similar to those of organic contaminants. The chronic water qualities, including organic, nutrient contaminants levels, show that the loading rates in 1998 are smaller than the past(1983, 1992). And this trend is more evident in industrial waste water streams than domestic waste water streams.