Abstract: The unaware radioactive material (URM) appeared in the society may induce potential deterministic effect, so it must be quickly dealt with. And the rapid and accurate identification for URM is the basis for the suggestion of reasonable treatment. An identification procedure for URM was developed, and the attributes of an URM were identified by the on site assay methods with in-situ HPGe γ spectrometry etc., and the laboratory testing methods with laboratory HPGe γ spectrometry, ICP-MS and density measurements. The results indicate that it is a kind of high pure depleted uranium metal with the ²³⁵U/²³⁸U atomic ratio of 0.454%.