Spheric chitosan sorbent was prepd. and used for removal of Am-241 from its aq. solns. The sorbability was detd. as decontamination factor and distribution coeff. The parameters depended on pH of soln. and were highest in alkaline solns. The thermogravimetric anal. coupled with differential scanning calorimetry and mass spectrometry were used to det. the thermal stability of the sorbent. Water and CO2 were found in the decompn. products.