We studied concentration of heavy metals in Sagunjatang. In this experiment was analyzed the concentration of heavy metals of boiled Sagunjatang, decoction and its ingredient herbal medicines. The concentration of heavy metals(As, Pb, and Cd) were analysed using ICP-AES, and Hg was analysed by mercury analyzer. The average concentration of heavy metals in Sagunjatang were as follows : In all ingredient herbal medicines (Glycyrrhizae Radix, Atractylodes Macrocephala, Poria Cocos and Jinseng) of Sagunjatang, As(arsenite) contents in ail samples was in the range of 0.369-0.723ppm, Cd(cadmium) was in the range of 0.000-0.085ppm, Pb(lead) was in the range of 0.059-0.871ppm and Hg(mercury) was in the range of 0.001-0.004ppm. In boiled Sagunjatang, the concentration of heavy metals(As, Pb, Cd and Hg) was in the range of 0.000-0.016ppm, respectively. In the decoction of herbal medicines after boiled, the concentration of heavy metals was in the range of 0.004-0.387ppm. These results suggest that Sagunjatang which we take is less harmful than herbal medicine itself, and there are more significant for using the decoction of herbal medicines.