Laccase from Pleurotus ostreatus was immobilized on different nanoparticles by physical adsorption and covalent binding. The immobilized enzyme on Na-clinoptilolite nanoparticles showed the highest recovered activity (71.75%) and thermal stability. X-Ray diffraction, surface morphology and the internal structure of the immobilization carrier (Na-clinoptilolite nanoparticles) were investigated. Compared to the free enzyme, the immobilized preparation exhibited higher optimum temperature, lower activation energy (Ea), lower deactivation constant rate (kd), higher t1/2 and higher decimal reduction time values (D) within the temperature range of 50–70◦C. The thermodynamic parameters (ΔH*, ΔG*, ΔS*) of irreversible thermal denaturation for the free and immobilized laccase were also evaluated. The values of enthalpy of activation (ΔH*), and free energy of transition state binding (ΔG*E−T) for substrate catalysis were lowered for the immobilized enzyme. Moreover, there was highly significant impact on improving the values of Vmax/Km, kcat, kcat/Km, and ΔG*E−S for the immobilized enzyme. The immobilized laccase from Pleurotus ostreatus NRRL 3501 on Na-clinoptilolite nanoparticles was evaluated for dye decolorization. In batch experiments the immobilized enzyme was able to decolorize the following dyes R. Blue 203 (97%), A. red 299 (100%), and Acid mix (89%) after incubation for 120 min. In repeated use the immobilized enzyme was able to decolorize the dye for 8 continuous cycles.