Invertase is an intracellular hydrolytic enzyme widely used in the inversion of sucrose into glucose and fructose. Both glucose and fructose are the primary compounds used as sweeteners in the food processing industries. In the present investigation invertase was immobilized in sodium alginate gel by entrapment method and the catalytic activity of immobilized enzyme was compared with the activity of native enzyme at variable pH and temperatures, Experimental findings revealed that for native enzyme optimum activity was at pH 4.2 and at temperature 30degreesC, while for immobilized enzyme it was observed at pH 4.8 and at temperature 50degreesC. Kinetic parameters K-m and V-max as well as catalytic efficiency of invertase was also determined for both the native and immobilized enzyme.