A mathematic model was established to analyze the effect of zone length and pass number on the uranium purification during zone melting process. The theoretically optimized condition was applied in the experiment and the elements of Al, Mo, W, Ni, Ca and C in uranium was chosen. The impurity concentration and inclusion distribution in uranium before and after purification were investigated by ICP-AES and OM. Results show that zone melting can remove the impurity elements in uranium. The total impurity concentration is reduced from 1189 μg/g to 402 μg/g. Zone melting has high removal efficiency to W, Ni, and C, but has low efficiency to Al and Mo. The inclusion decreases in size and enriches along the melting direction.