Abstract: A radiochemical procedure for separation of ~(79)Se from HLLW based on ion-exchange chromatography and precipitation is developed. The HLLW sample is first loaded to an anion exchange(column) and then eluted with 8 mol/L HCl.The effluent is transferred to 0.75 mol/L HNO_3 medium,and then let it pass a mixed ion exchange column and eluted with 0.3 mol/L HNO_3. After addition of Na_2SeO_3 carrier and holdback carriers for ~(137)Cs,~(90)Sr,~(125)Sb,etc.,the ~(79)Se is precipitated with Na_2SO_3 as elemental Se from the effluent.After washing,the Se precipitate is dissolved in nitric acid.Aliquots of the final solution are measured by HP Ge gamma spectrometry,liquid scintillation spectrometry and ICP-MS.The decontamination factors for interfering radionuclides are estimated.The final recovered ~(79)Se is roved to be raiochemically pure.The overall recovery for ~(79)Se is about 53%.