Abstract:Soluble mercury contents in Baochi San, Xiaoer Zhibon Ding and Xiaoer Baishou Dan have been determined using dithizone method. This method has the advantages of short digestion time, clear digestion end point, simple operation and reproducible results. The recovery rate ranges from 98.4 to 103%. The data obtained can be used as a reference for controlling soluble mercury contents in Chinese traditional patent medicines containing cinnabar.