Displacement-extraction of tracer concentrations of210Po in 1.0M (H, Na)NO3 solutions has been studied by using copper dithizonate–CCl4 solutions. Furthermore, based on the results of the displacement-extraction of polonium, a mixture of210Po,210Bi, and210Pb of tracer concentrations in 1.0M (H, Na)NO3 solutions could be satisfactorily separated with successive extractions by copper dithizonate–CCl4 and dithizone–CCl4 solutions in acidic conditions.