Purification of yttrium from dysprosium, holmium, erbium and ytterbium has been studied on the strongly basic anion exchenger Dowex 1×4 in an acetate form and for comparison in an iminodiacetate form. The rare earth element solutions complexed with iminodiacetate acid Ln (imda)2were separated using frontal analysis. The obtained results show the significant effect of en anion exchanger form on separation of Ln(imda)2complexes. An acetate form of the anion ex changer proves particularly effective and economical in yttrium separation from dysprosium, holmium and erbium but IDA form for yttrium separation from ytterbium.