The nature of species formed in the extraction of lanthanides Ln(ΙΙI) (where Ln = Tb, Dy, Ho, Er, Tm and Yb) with 5,7-dichloro-8-hydro xyquinoline (IIL)) in CHCl 3 from water or water-methanol phase was examined. It was stated that during tle extraction from water phase the chelates LnL3 (Tb, Tm), seven-coordinated self-adducts LnL3--HL (Er, Ho) or both types of these species (Dy, Yb) were extracted. In the presence of methanol (MeOH) in the aqueous phase the eight-coordinated mixed species of the type LnL3 • 2ΜeOH were observed.