Abstract: Visible spectroscopy is used to study the U4+ cation and some complexes with Cl- at high chlorine concentration. Infrared and visible spectroscopy are used to study the complexes of U(Ⅳ) with Cl- - sorbed on anion exchange resin from HC1 solution. Experimental results seem to indicate that the predominant species sorbed on anion exchange resin is UCl2 6-. The dependence of distribution ratio of U(Ⅳ) on the concentration U(Ⅳ) in anion resin is in agreement with the assumption that U (Ⅳ) species sorbed on anion resin is UCl2 6-.