AbstractA method using Gallein as indicator for the direct titration of lanthanum with disodium salt of EDTA was proposed. With this indicator, lanthanum ion can be titrated at thepH of 5.5 to 6.5, using hexamethylenetetramine as buffer.At the end point, the violet color disappeared, giving rise to a red color. The interference of approximately equimolar concentration of various foreign ions was observed.Rare earth metal may be titrated along with lanthanum under the same conditions, as shown by the presence of cerium ion.