Abstract: Determination method of ~(147)Pm in high-level liquid waste is set up. The method is composed of extraction RE and Am and Cm from 0.1 mol/I HNO_3 aqueous solution containing samplc with 0.5 mol/l HDEHP-η-heptane, reextraction with 5.5 mol/l HNO_3, subsequently chromatography with a column filled HDEHP-levextrel for separation of RE and Am and Cm when 0.07 mol/l DTPA-1 mol/l lactic acid(pH3. 12) is used as eluant and HPLC for separating ~(147)Pm from other rare earths when α-HIBA was used as eluant. The radioactivity of ~(147)Pm is measured by liquid scintillatin counter.