Abstract: An analytical method for the determination of Li, Na, K and Cs in uranium dioxide is developed.The uranium dioxide powder is dissolved in nitric acid, then the sample solution is passed through a TBPlevextrel chromatographic column. 5. 5 mol·l~(-1) HNO_3 is used as eluant. The eluate is analysed by air-C_2H_2 AAS for Li, Na and K, and air--C_2H_2 AES for Cs, respectively. The concentration range deter-mined Li, Na, K and Cs in UO_2 is 2×10~(-6)--20×10~(-6) for 0. 5 g sample. The recovery is from 96%to 103% and RSD is 3%, 5%, 7% and 6% for Li, Na, K and Cs, respectively. This method is sim-ple and reliant. It was accepted as a national standard analytical method in China now.