Abstract: A method for the determination of Am in irradiated fuel is reported. Afterpreliminary separation by HDEHP Levextrel. Am is separated and purified bysynergistic extraction with 0.05 mol/l PMBP-0.25 mol/l TBP. A stable chemicalyield of (95.6±0.6)% for Am is obtained. The decontamination factors for U,~(239)Pu are all over 10~6 and those for ~(95)Zr-~(95)Nd, ~(144)Ce and ~(147)Nd all over 10~4; for~(90)Sr over 10~5; for ~(137)Cs over 10~6.