Enhanced chitinase secretion was demonstrated in batch fermentation process by immobilizing a novel bacterial isolate SJ602 in alginate beads. The phylogenetic data affirmed the identity of the SJ602 as Stenotrophomonas maltophilia strain. Optimization of the conditions suggested the alginate concentration of 4% at a pH range of 6.0-7.0 and temperature of 37 °C, are the more convenient conditions for achieving maximal enzyme activity of immobilized cells. Amendment of alginate with 5% skimmed milk powder added greater stability, and also maintained the viability of bacterial cells inside the entrapped alginate beads. Thus, the alginate immobilization, described above, improve the bacterial life and the chitinase activity as compared to non-immobilized bacterial cells. The results described the effect of the biodegradable polymers as the nutrient source in maintaining the critical biomass and enhanced stability during long term storage at ambient temperature. The study showed S. maltophilia SJ602 as a potential candidate for agricultural and biotechnological applications.