Extraction of micro amounts of rare earth elements(III) (REE) from nitric acid solutions with diethyl 2-[(diphenylphosphoryl)methoxy]-5-ethylphenylphosphonate (I) in dichloroethane and ionic liquid, 1-butyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide has been studied. The stoichiometry of extracted complexes has been determined, the effect of HNO3 concentration in aqueous phase on the efficiency of metal ion recovery into organic phase has been considered. It has been found that compound I in dichloroethane extracts REE(III) less efficiently than its analogs with phenyl and butyl substituents at the phosphorus atom. It has been shown that the efficiency of REE(III) extraction with compound I from nitric acid solutions increases considerably in the presence of ionic liquid in organic phase.