U-10wt%Zr alloy powders are the raw material of the uranium alloy fuels by a powder metallurgic process in nuclear reactor. In this work, U-10wt%Zr powders were prepared by a hydriding-dehydriding process, and the prepared powders were studied by XRD and SEM. The results show that the pretreatement of U-10wt%Zr alloy is a key issue to obtain U-10wt%Zr powders. During the hydriding-dehydriding process, the absorbed hydrogen of U-10wt%Zr alloy increases with the cycle number increasing. After 10 cycles, the absorbed hydrogen reaches a stable value. U-10wt%Zr alloy were heated to desorb the hydrogen at 650 oC, and then U-10wt%Zr alloy powders were obtained. XRD results show that U-10wt%Zr alloy powders are still g phase, indicating that during preparation, the phase transformation process does not occur. SEM observation suggests that the particle shape of U-10 wt%Zr alloy powders is nonuniform, but particle size is less than 150 mm, while some are below 100 mm