Abstract: Fenton reagent oxidation experiments were conducted to test its feasibility in pretreatment of radioactive spent ion exchange resin. The effects of reaction conditions such as the dosage of H₂O₂ and Fe²⁺, reaction time(t)and reaction temperature(θ)were studied in term of chemical oxygen demand (COD) removal efficiency. The optimum operating conditions determined by the orthogonal experiments are as follows: c₀(H₂O₂)=4.0 mol/L, c₀(Fe²⁺)=20 mmol/L, θ=95 ℃ and t=4 h at pH=2.5. Under optimum operating conditions, approximately 100% decomposition efficiencies can be achieved for three 50 g uraniumcontaining wet resin samples. The COD is reduced from 8.0-10.0 g/L in the initial solution to 0.2-0.3 g/L in the residual solution . At the same time, the concentration of uranium in the tail-gas absorption solution don’t remarkably increase. The study results show that the pre-treatment of industrially generated radioactive spent ion exchange resin by Fenton’s reagent can entail very effective degradation of the resin. 