Abstract: AO-MWNTs were obtained through multi-walled carbon nanotubes (MWNTs) modified by amidoxime group, and characterized by transmission electron microscope (TEM) and fourier transform infrared spectrometer (FTIR). The adsorption experiments of uranium on the raw-MWNTs and AO-MWNTs were studied under different conditions. The results show that the adsorption capacities of uranium on raw-MWNTs and AO-MWNTs primarily increase and then decrease over the range of pH=2.8, and reach the maximum at pH=5. With the increase of initial concentration of uranium, the adsorption capacities of uranium on the two materials gradually increase. When the initial concentration of uranium is 10 mg/L, the adsorption of uranium on AO-MWNTs balances after oscillating 30 min, and the adsorption capacity reaches 18.93 mg/g, while the raw-MWNTs tend to be stable after 60 min, and the adsorption capacity is 9.59 mg/g. The adsorption capacity of uranium on AO-MWNTs can be described by Langmuir and Freundlich models, and the theoretical maximum adsorption capacity can reach 106.38 mg/g.