For the production of dextran a high enzyme active strain of L. mesenteroides NCIM-2198 was selected. To increase the yield of dextran, media was optimized using Resonse Surface Methodology (RSM). A Central Composite Design (CCD) with four variables was used to determine the optimum combination of the variables. A total 31 runs were generated by varying the concentrations of four media components sucrose, peptone, yeast extract and K 2HPO4 and yield as a response. The temperature for the production medium was kept at 30°C and the pH of the production medium was 7.0 before sterilization. The optimal conditions were obtained; condition 1: sucrose 10.157 g/100ml, yeast 1.611 g/100ml, peptone 0.573 g/100ml, K 2HPO4 1.845 g/100ml and condition 2 as: sucrose 10.313 g/100ml, yeast 1.000 g/100ml, peptone 0.718 g/100ml, K2HPO 4 1.000 g/100ml. Under these conditions, the model predicted a dextran production of 3.493 g/100mL and 3.466 g/100ml respectively. Validation of the optimization showed that dextran production of 3.186 g/100ml and 3.157 g/100ml was observed under optimal conditions 1 and 2 respectively.