Abstract: In order to study the adsorption of uranium on Fe(OH)₃ colloid in situ leaching of uranium, the Fe(OH)₃ colloid was prepared in absolute ethanol, and the adsorption performance of uranium on Fe(OH)₃ colloid was detected. The effects of pH value, initial uranium concentration, and the contact time were analyzed. As for the adsorption dynamics, the pseudo-first-order, composite-second-order and Elovich dynamic models were comparatively calculated and discussed. The results show that the Elovich dynamic model is fit to describe the adsorption of uranium on Fe(OH)₃ colloids. As for the adsorption thermodynamics, the Freundlich and Langmuir adsorption isotherm models were applied to analyze and fit the experimental equilibrium data. It is found that the equilibrium data agree well with the Freundlich model. In conclusion, the adsorption of uranium on Fe(OH)₃ colloid belongs to the single layer physical adsorption of uneven surface. The laser particle size and SEM analysis results reveal that the Fe(OH)₃ colloids show a good adsorption performance, and the surface adsorption takes precedence in the adsorption process.