Abstract: A method of chromatographic adsorption accompanied with complex compound formation was used for purifying alkali earth metal compounds from heavy metal impurities. This method provides a means to remove the following impurities to an extent of ppm level, such as Fe<0.4, Co<0.1, Cu<0.5, Ni<0.7, Pb<0.2, Zn<～0.4 ppm. This method enables purification to be accomplished with a higher efficiency and in a larger capacity than that of other methods.The efficiency of several complexing agents and the optimum processing conditions have been studied.