Abstract: A study on extrection cf trace U(Ⅵ) with PMIP-loaded pclyurethane foam from water is described. The effect cf equilibrium time, concentration of acetic acid, cortent of U(Ⅵ), temperature and foreign ions is examined. Uranyl acetate can be quantitatively extracted by PMBP-loadod foam from 0.05.Macetic acid solution. Dis over 4.65×10⁴and enrichment factor is over 4500. Anew procedure for preconcentration of trace U(Ⅵ) from large volume of water has been developed. Aprocedure for the PMBP foam extraction-arsenazo Ⅲ spectrophoto-metric determination of U(Ⅵ) at ppb level is cstablished.