Tannery wastewater contains high level of protein, which, as a macromolecule takes longerrnresidence time for its microbial degradation. The objectives of this study were to see therneffect of adding protease and bio-augmentation of proteolytic organisms on proteinrnhydrolysis and on total nitrogen removal rate using anoxic/oxic lab-scale reactor feededrnwith synthetic wastewater. Eighty five proteolytic organisms were isolated from tanneryrnwastewater sludge sample of which proteases extracted from three best isolates (ETY-19,rnYE-25 and YE-33). The temperature and pH characteristics of proteases of the threernselected isolates showed optimum activity at around neutral pH range and at mesophilicrntemperature. Protease from YE-33 was used to see the effect of adding enzyme on proteinrnhydrolysis and the same organism was used to test the effect of bio-augmentation onrnprotein hydrolysis. Ammonium production, total nitrogen and chemical oxygen demandrn(COD) removal were determined for 120h experimental time. Increasing protease activityrndidnâ€™t considerably affect the overall COD removal where, removal efficiencies were 89-rn91%, 89-90% and 90-91% for no enzyme, 10 and 30U/ml protease supplementsrnrespectively. Anoxic system ammonium concentration increased from 65-70mg/l, 61-rn109mg/l and 74-153mg/l for the non enzyme supplemented, 10 and 30U/ml proteasernsupplements respectively. The 120h average total nitrogen removal efficiencies were 55.4-rn56.8%, 54.5-61.3% and 54.7-73% in the non enzyme supplemented, 10 and 30U/mlrnprotease supplemented experiments respectively. In the bio-augmentation experiments inrnaddition to colony forming unit count Ammonium production, total nitrogen and CODrnremoval efficiency were determined for 120h experimental time. There was very littlernvariation in COD removal efficiencies where 90-93%, 89-91% and 90.5-91.5 % CODrnremoval efficiencies observed in non augmented, 10 x107 and 10x109 cfu/ml cell densityrnaugmentations respectively. Ammonium concentrations in the anoxic tank were 77-79mg/l,rn78.2-100mg/l and 101-104mg/l in the non augmented, 10x107 and 10x109 cfu/mlrnaugmentations respectively. Little improvement 56-58%, 58-64% and 65.68% in totalrnnitrogen removal efficiencies were observed in the non augmented, 10x107 and 10x109rncfu/ml cell density augmentations respectively. In general exogenous protease andrnproteolytic bio-augmentation found to improve protein hydrolysis and nitrogen removalrnrates.