Growth media employed to culture Aspergillus niger for the production of enzyme were developed and fermentation conditions was optimized through various trials. Substrate water ratio, different nitrogen source and concentration of nitrogen source were optimized. It was observed that addition of 25% potato extract and 0.3% urea enhanced the production of ?- amylase by Aspergillus niger. Maximum enzyme activity was observed (102.59 IU/ml/min) in flask level at pH 4 and 37ø C temperature. These optimized conditions of growth media was again used in Air-Lift fermenter and determined the activity (116.5 IU/ml/min) that is greater than flask level. This is due to proper aeration and proper temperature in Air-lift fermenter.