Abstract: A high sensitive spectrophotometric method was develop for the determination of Europium.Europium reacts with crystal violet in the presence of NH₃(pH 10.10±0.05) to form a violet complex.The ion association complex exhibits maximum absorption at 590 nm with an apparent molar absorpbtivity of 1.8×10⁵ L/(mol·cm).Beer'law is obeyed in the range of 0.15~1.2 mg/L for Eu³⁺.The molar ratio of the components of Eu:CV is 1:2.The composition of association complex has been discussed.The proposed method has been used for the determination of Eu³⁺ in imitative samples with satisfactory results.