Modified diatomite was prepared by chemical treatment with 1-ethyl-3-methylimidazolium chloride solution. The properties of the modified diatomite have been studied using scanning electron microscopy, infrared absorption spectroscopy, thermogravimetric technique, zeta potential and carbon content analyzers. The adsorption of uranium(VI) from aqueous solutions onto the ionic liquid modified diatomite was studied using batch adsorption experiments. The parameters influencing the uranium adsorption, such as contact time, pH of solution, and initial uranium(VI) concentration were studied. Most of the uranium is adsorbed in the first 5 min. The maximum adsorption of the modified diatomite toward uranium under experimental conditions was 88 mg/g.