Surfactin was produced from rice mill polishing residue by submerged fermentation using B. subtilis MTCC 2423. Nutrient addition was not required due to their inherent presence in the substrate. Carbohydrate utilization, growth and surface tension were correlated. The Logistic and Gompertz model fitted the experimental data with R2 > 0.99. Foam fractionation was used to concentrate and purify surfactin with recoverable yield of 4.17 g/kg RMPR from foamate after three stages (Table 1). ESIMS/MS showed a predominance of molecular weight 1076. Dramatic reduction in surfactin cost can result by using RMPR as substrate for its large scale production.