Abstract: In order to master the rule of surface activity of radioactively contaminated materials commonly used in uranium mining and metallurgy, the characteristics of surface activity, surface morphology and the form of uranium were studied with stainless steel, plexiglass and rubber soaked in different uranium nitrate milling concentrations solution for 26 days. The results show that the surface activities of three kinds of materials do not change significantly over time as the mass concentration of uranium solution is 10.22 mg/L; the surface activity value of each material increases gradually over time, as the uranium mass concentrations are 563.58 mg/L and 25.54 g/L, within 26 days. In addition, the contamination degree of three kinds of materials from large to small in the order is rubber, stainless steel and plexiglass. The increase of activity on the surface of the sample is mainly due to the corrosion of samples, which leads to the deposition of uranium on the surface of the sample. The forms of uranium on the sample surface are mainly UO₂(NO₃)₂•6H₂O and a small amount of UO₃.