Among the problems of protecting the environment from radioactive contamination, the reduction of radioactive releases by improving monitoring, decontamination, and burial methods is one of the most important. Natural sorbents are gaining increased significance for solving this problem. Among these, zeolites deserve special attention since they have sufficient sorptive capacity, are highly radiation resistant, are widely distributed exhibit selectivity and are inexpensive. In the present work we determine experimentally the sorptive characteristics of clinoptilolite as a function of various factors and demonstrate that clinoptilolite is capable of sorbing Ce(IV) over a wide pH range. (Author).