This study was carried out to provide the basic information for the water quality management of the Sumjin River Basin. The Chooryeongchon stream watershed was selected and the parameters representing water quality were investigated from May 1999 to September 2002, periodically. Yearly mean runoff ratio to the rainfall amount of the watershed was analysed as 26.6~58.8%. Temporal variation of water quality constituents such as water temperature, pH, EC, total nitrogen, total phosphorus were analysed. The result showed that pH ranged 5.7~7.7, EC 54~167 μS/cm, COD 0.8~18.1 mg/L, respectively. Total-N and total-P concentration ranged from 0.89 to 5.19 mg/L and from 0.0004 to 0.030 mg/L, respectively. The relationships between runoff and mass load were derived and showed high linear relationships.