Abstract: Zirconium is adsorbed and separated by high adsorption activity silica gel in simulated HLLW. The selective adsorption mechanism is analyzed. The results show that adsorption selection of silica gel for zirconium is strong because zirconium has higher positive charge. The static adsorption capacity of zirconium is 0.344 mmol/g; the desorption rate of zirconium on silica gel by 0.2 mol/L H 2C 2O 4 is more than 99 %; The numbers of hydroxy groups (-OH) on the surface of silica gels made in laboratory are 6.5/nm 2 which provide more adsorption activity sites.