Abstract: By using n octanol(40%) kerosen as diluent, the extraction behavior of Am(Ⅲ) and Eu(Ⅲ) from nitric acid solution is studied with N,N,N’,N’ tetrabuty1 3 oxa pentanediamide(TBOPDA),N,N,N’,N’ tetraisobuty1 3 oxa pentanediamide(T i BOPDA) and N,N,N’,N’ tetrabuty1 3,6 dioxa octanediamide(TBDOODA). The distribution ratios of Am and Eu increase rapidly with HNO 3 conentration in the range of c (HNO 3)<3.0 mol/L,then increase slowly. The composition of the extraction complexes and the extraction mechanism are examined. The extraction equlibrium is expressed. It is elucidated indirectly that the extraction is neutral complexation by measuring the electroconductivity of organic phase loaded with metal ion. Am(Ⅲ) and Eu(Ⅲ) in organic phase can be stripped by dilute nitric acid or by water.