It is the purpose of this study to investigate the change of stream water quality in upper stream of Dongjin river, and to give the basic information for the conservation of water quality. Water samples were taken periodically at 9 sampling sites during 8 months from March to October in 2002. The results of this study were as follows : 1. The water temperature and pH of stream water were ranged 9.0~29.4℃, 6.48~9.33, respectively. The COD values of stream water was ranged from 0.60 to 19.06. The contents of T-N and T-P mainly affected by the livestock wastes, and agricultural activity were 1.88~6.74 mg/L, ND(not deleted)~0.50 mg/L, respectively. 2. The SS, DO and BOD values of stream water were ranged 0.4mg/L~274.0mg/L, 0.5~6.0 mg/L, and 7.3~13.7 mg/L respectively. 3. The cation is one of the important components in analysis of stream water quality. The contents of analysis, Ca++, Mg++, Na+ and K+ were ranged 1.96~11.08 mg/L, 1.21~6.16 mg/L, 3.38~18.44 mg/L, 1.12~7.96 mg/L, respectively. SAR was ranged 0.31~1.63 below 2.0. The contents of cation showed in the order Na++>Ca++>K+>Mg+. 4. The contents of heavy metal Zn, Cu, and Pb were ND~0.071 mg/L, ND~0.012 mg/L, and ND~0.043 mg/L, respectively. Cd was not detected in all samples. 5. As a result of these researches showed water quality in upper stream watershed of Dongjin river more affected by livestock wastes and living sewage than agricultural activity.