Pectinase fromAspergillus tamaristrain Redpep4 was immobilized on Zr-treated pumice by adsorption. The support was characterized by FTIR,SEM, XPS, and EDS analysis. The effects of various factors on immobilization such as the initial amount of enzyme (25 mg, 50 mg, 150 mg, and 300 mg), immobilization time (1 hr, 3 hr, 6 hr, and 18 hr), and temperature (4 degrees C, 25 degrees C, 40 degrees C, and 50 degrees C) were examined. The maximum amount of adsorbed pectinase was determined as 229 mg/g support. The optimal pH for activity shifted from 6.0 to 7.0 after immobilization; however, the optimum temperature remained unchanged at 50 degrees C. The immobilized pectinase had the higher thermal stability than the free enzyme. It has also improved reusability and sustained 72% of initial activity after 11 batch reactions. Immobilized pectinase could have potential applications in fruit juice industry with improved thermal stability and reusability. Practical applications Pectinase has wide applications in juice industry such as reduce juice viscosity, improving press ability of the pulp, disintegrating the jelly structure and increasing the fruit juices yields. In this study, thermal stability and reusability of pectinase fromAspergillus tamaristrain Redpep4 were improved with immobilization on Zr-treated pumice. The obtained immobilized pectinase presented great potential application to the fruit juice industry for clarifying juice.