A coal-water slurry was prepared by mixing 250ml of distilled water and a given amount of Datong Coal. The concentrations of slurry prepared was 0.596, 5.66 and 23.1wt%. The slurry was stirred for 3h. One ml of the slurry was taken by a syringe every 20min to investigate the elution rate of inorganic ions. Water-soluble inorganic matters in coal was attempted to quantitatively analyzed using ion chromatography. In comparison with ICP-AES, ion chromatography could be a method much easier to operate and cost effective. Three types of columns, YK-421 (HITACHI) for cations analysis, #2740 for anions analysis, and #2617 (HITACHI) for trace elements analysis, were used. It was found that cations were mostly eluted within 20min, while the elution of SO_4^<2-> continued up to 80min, leading to a decrease of pH from 5.3 to 2.6.