Abstract: A flow coulometric detector was applied to a study of the separation of heavy metal ions by cation-exchange chromatography using tartrate,lactate and citrate as the eluents.The separation of a six-component mixture of metal ions (copper,zinc,nickel,cobalt,cadmium,and manganese) was completed within one hour under suitable conditions.The effects of composition and flow rate of the eluents on the retention time and column efficiency was investigated.The relation of plate height and flow rate of the eluents was agreeable to the Snyder equation.It was observed that the electrolytic efficiency varied with the kind of ions and the size of the sample.The method was applied to the determinations of copper and zinc in a brass and waste water.Aflow coulometric detector was applied to a study of the separation of heavy metal ions by cation-exchange chromatography using tartrate,lactate and citrate as the eluents.The separation of a six-component mixture of metal ions (copper,zinc,nickel,cobalt,cadmium,and manganese) was completed within one hour under suitable conditions.The effects of composition and flow rate of the eluents on the retention time and column efficiency was investigated.The relation of plate height and flow rate of the eluents was agreeable to the Snyder equation.It was observed that the electrolytic efficiency varied with the kind of ions and the size of the sample.The method was applied to the determinations of copper and zinc in a brass and waste water.