Abstract: The separation condition of strontium from fission products using SISAK system and yttrium from Sr-Y mixture was studied. The separation process was optimized.The method that separates Sr-Y after separation of strontium from fission products was selected, which was based on the half-life difference between ⁹⁴Sr and ⁹⁵Sr. Combined the fast chemistry separation and decay characteristic, ⁹⁵Y was separated successfully in the mini-reactor in CIAE. The recommended technological process was given