The potential of prepared alginate biopolymers as a natural, economic, effective, non-toxic biosorbent was investigated for the recovery of thorium ions in this study. The experiments were carried out to study the effects of various physico-chemical parameters on biosorption and desorption of thorium. The biosorption process was examined by various isotherm models and equilibrium data were successfully described by a Langmuir model very well. The monolayer biosorption capacity was found as 169.50mg/g. The thermodynamic parameters such as variations of enthalpy, entropy, and Gibbs free energy for thorium biosorption were also defined and the results suggest that endothermic nature of the process. The prepared alginate biopolymers exhibit high uptake capacity and regeneration potential for biosorption of thorium.