Sorption of Cs, Co and Eu on coal (oxihumolite and its parent lignite artificially oxidized to increase degree of oxygen functionalities) in mixture with chitosan was studied using radiotracer method. Distribution coefficients (Kd) increasing in the order Cs Co Eu reflected increasing charge of a metal cation and its increasing ability of complexation with coal humic substances(HS). In acidic media, Kds increased with pH due to dissociation of the HS binding sites. In neutral media, Kds of Eu (for oxihumolite also Co) decreased with pH due to formation of soluble HS complexes. An improved sorption efficiency of the coal sorbents at neutral pH was obtained in mixture with chitosan, namely for oxihumolite at sorption of Eu and Co. Addition of chitosan prevents deterioration of the sorption ability probably via removing the HS complexes from solution by formation of an insoluble complex with chitosan.