The characteristics of high density U-Mo alloy powder solidified rapidly by the centrifugal atomization process have been examined. The results indicate that most of the atomized U-Mo alloy particles have a smooth surface and near-perfect spherical shape. The atomized powder, irrespective of particle size, is found to be single phase gamma-U alloy with isotropic structure and non-dendritic grain. The continuous cooling DSC trace of U-2 wt% Mo alloy shows a small, broad endothermic peak originated from the formation of alpha-U phase and U2Mo phase, whereas that of U-10 wt% Mo alloy shows no peak over all temperature ranges associated with the decomposition of gamma-U phase. The gamma-U phase of U-2 wt% Mo powder is decomposed as the alpha-U phase and the U2Mo phase after an annealing treatment at 400 degrees C for 100 h. But the gamma-U phase of atomized U-10 wt% Mo powder remains as it was.