Normally, abundant inorganic anions such as chloride and sulfate…ect have not being considered in the general assessment of surficial water quality while they coexist with other spices in various forms. However, there obviously exists the correlation between the presence of these anions and water property and so the water pollution level in water environment. The index of pollution (IP) is based on the so-called “salt ratio” between concentrations of chloride and sulfate as sulfur ([Cl-]/ [SO42- -S]) could be used as the parameter of contamination level of water by human activities. In case of Han River, an important water supply source, the performance of COD, Cl, SO4 and Cl/ S ratio indicated the feasibility of using this new parameter in water evaluation after samples had been periodically collected and tested with ion chromatography and test kit. The result showed the correlation between contamination level and salt ratio. Water quality of area was regarded to be clean in case salt ratio less than 2, otherwise, to be more polluted in term of general evaluation.