This study evaluates the influence of growth parameters such as pH, temperature, Carboxy Methyl Cellulose (CMC) concentration and agitation on cellulase production from three bacterial strains, viz., Achromobacter xylosoxidans BSS4, Bacillus sp. BSS3 and Pseudomonas sp. BSS2 isolated from the wood-yards on Kallai river bank in Kerala. Production of cellulase by these isolates was detected using basal salt medium (BSM) with 0.5% CMC as supplement, and CMCase activity was confirmed by iodine test. Dinitrosalicylic acid method was employed for assaying the cellulase production by measuring the amount of glucose liberated in μmol/mL/min. Maximum enzyme production from Pseudomonas sp. BSS2 was at pH 8, 37℃ with 1% CMC and 150 rpm, and cellulase production increased from initial 49.84 U/mL to 91.28 U/mL after optimization. The highest enzyme activity from Bacillus sp. BSS3 was at pH 9, 37℃ with 1% CMC, 150 rpm, and cellulase production increased from initial 26.05 U/mL to 104.68 U/mL after optimization. The maximum enzyme production from A. xylosoxidans BSS4 was at pH 7, 40℃ with 0.5% CMC and 150 rpm, and cellulase production increased from initial 55.28 U/mL to 68.37 U/mL after optimization. Thus among the three isolates, Bacillus sp. BSS3 showed maximum enzyme yield which can be explored for further scale up studies with an industrial perspective.