The synthesis and characterization of (Ph4P)(2)UO(2)I(4)center dot 2NCCH(3) is reported. The UO2I42- anion is not only the first unambiguously characterized anion containing a uranium(VI)-iodine bond, but is also the last member of the UO2X42- (X = Cl, Br, I) series to be unambiguously identified and structurally characterized, in contrast to salts of the UO2Cl42- and UO2Br42- anions, which have all been thoroughly investigated and structurally characterized. (Ph4P)(2)UO(2)I(4)center dot 2NCCH(3) was characterized using IR, Raman, H-1, C-13, and P-31 NMR spectroscopy as well as X-ray diffraction. In addition, a computational investigation of the UO2I42-anion was undertaken and compared with the experimentally observed structure.