Ion exchange resins are used in various industries, including the purification of radioactive wastewater at nuclear power plants. Spent ion-exchange resins are heterogeneous radioactive low-level waste in the form of a cross-linked organic polymer beads. Such resins not always can be reused and regenerated. Therefore, there is a problem of their disposal in order to reduce the potential danger to the environment and human health. However, traditional technologies for the disposal of radioactive ion exchange resins are relatively expensive. In the present study, an attempt was made to solve the problem of spent ion-exchange resins utilization by the example of the sulfonic acid cation exchanger KU-2×8 oxidative destruction using the Fenton reaction. The decomposition of the cation exchanger was carried out with 5-25% hydrogen peroxide in the temperature range 348-368 K. The influence on the process of such factors as the process temperature and the concentration of hydrogen peroxide was estimated...