Pullulanase showed significant improvement in thermal stability after covalent immobilization on Duolite XAD761. Optimum temperature of immobilized enzyme was 60°C, which was 10°C higher than the free enzyme. Apparent K m values for pullulan, soluble starch and dextran were 4.4, 20 and 50mgmL −1 , respectively. Mn 2+ and Ca 2+ showed 2.0- and 2.2-fold increase in enzyme activity. Activation energy (Ea) of immobilized biocatalyst was 22.38kJmol −1 . Thermodynamic parameters (ΔH*, ΔG*, ΔS*) for irreversible inactivation of immobilized pullulanase at different temperatures (60–70°C) were also determined. D-value was maximum (95.95h) at 60°C and temperature quotient (Q 10 ) was 1.29. Immobilized biocatalyst was effectively used for pullulan hydrolysis in a batch system. Stationary phase in hydrolysis (95.70±1.36%) was reached after 300min at 125rpm. Pullulan hydrolysis yielded 4.21±0.06% reducing sugars under optimal conditions. Immobilized biocatalyst was successfully recycled for 33 batches, but the enzyme activity was reduced to half after 25th cycle.