Abstract: Lime-polyaluminum chloride （PAC） coagulation process,lime-aluminum chloride chemical precipitation,and electrodialysis process were used to remove sulfuric acid radical （SO<SUP>2-<SUB>4</SUB></SUP>） from mine water.Results showed that: SO<SUP>2-<SUB>4</SUB></SUP> removal rate is low with lime-PAC coagulation process due to the effect of solubility product of lime itself.Although SO<SUP>2-<SUB>4</SUB></SUP> removal rate can reach more than 95% with lime-aluminum chloride chemical precipitation,impurity ions are easily induced.Electrodialysis process for mine water treatment has advantage of simple process,better SO<SUP>2-<SUB>4</SUB></SUP> removal effect,and without the introduction of impurity ions.It is a more economical and feasible method presently.