Because of excellent properties, U - Zr alloy will be used widely more and more in the future. To meet the large amounts of U - Zr alloy routine analysis, Energy Dispersion X-ray Fluorescence was used to determine zirconium content in U-Zr alloy in the present study. The thin-layer samples were prepared through dissolution, transferring and drying. Compared to traditional methods, this method shares simplicity, rapidness, as well as accuracy. It can be used in the determination of Zr content in the range of 6%-18% in U-Zr alloy. The relative standard deviation (RSD) (n=6) is not above 1.0%. The extended-uncertainty (k=2) is not above 3%.