Two modified mesoporous silica (KIT-6) materials for absorbing uranium(VI) were prepared respectively via post-grafting of 8-hydroxyquinoline and 8-hydroxyquinoline onto surface of KIT-6, which were characterized by FT-IR, NMR, TEM, and sorption/desorption analysis. Effect of pH values, contact time, ionic strength, solid-liquid ratio, temperature, and coexisting ions on sorption behavior of the modified KIT-6 were also investigated. Typical sorption isotherms (Langmuir and Freundlich) were used to determine the sorption process and the maximum U(VI) sorption capacity. The results indicate that the two modified KIT-6 exhibit better selective sorption of U(VI) as compared to the original KIT-6.