Abstract: In order to measure ¹⁸²Hf in some environmental samples by accelerator mass spectrometry(AMS), a method for separation of hafnium(Ⅳ) from tungsten(Ⅵ) has been developed by solvent extraction using N₁₉₂₃ and TOA as extractants. The effects of different mineral acids, acid concentration, complexing agent concentration, extractant concentration and diluent on the extraction behavior of both elements were investigated. The recovery of hafnium(Ⅳ) is better than 90% and the decontamination factor for milligram amounts of tungsten(Ⅵ) is 4.4×10⁷ using the present separation procedure.