The study aimed at isolating and screening cellulolytic bacteria from local habitats for the production of cellulase. A number of cellulolytic bacteria were isolated from soil, melon and gut of herbivore (goat) by applying serial dilutions and culture methods. Two of the isolates, CB-2 from soil and CB-3 from melon produced sufficient amounts of cellulase on screening and were further investigated upon. Applying different biochemical tests, CB-2 and CB-3 identified as Bacillus subtilis were used for the flask-scale production of cellulase through submerged fermentation. A parametric study was also conducted to evaluate the optimized culture conditions such as temperature, pH, concentration of the carbon source, nitrogen source and inoculum size and concentration of the carbon source for maximum enzymatic yield. Results revealed the highest cellulolytic activity (CMCase) with 120.321 U/ml and FPase activity with 1.076U/ml by CB-2 strain followed by CB-3. Optimum temperature and pH of the medium for cellulase production was 37.5oC, pH and 9 respectively, with 2% untreated cotton stalk as carbon source, yeast as organic nitrogen source and ammonium sulphate as inorganic nitrogen source with 3% inoculum size. By applying ANOVA, a significant difference (p<0.05) among values was found
