Solvent extraction of La3+ and Ba2+ by N, N, N',N'-tetra(n-octyl)diglycolamide (TODGA) from aqueous solutions in twelve imidazolium- based ionic liquids (ILs), 1-alkyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide/bis(perfluoroethylsulfonyl)imide ([C(n)mim][NTf2]/[BETI], n = 2,3,4,6,8,10) were investigated. The corresponding extraction efficiencies were found to be dependent on concentration of TODGA used, the acidity of aqueous phase, alkyl chain length on IL cation, and IL anion as well.