Abstract: In the present study, the influence of aeration on α-amylase production kinetics by Bacillus amyloliquefaciens was studied in both shake flask and bioreactor. In the first optimisation step in shake flask cultures, different cultivations were conducted to study the effect of aeration on the kinetics of cell growth and amylase production by changing the shape of flask (i.e., baffled and non baffled flask), working volume of fermentation media and shaking intensity. In shake flask cultures, the maximal enzyme production of about 2200 μkat L-1 was obtained in baffled Erlenmeyer flask agitated at 200 rpm and 10% working volume. Further improvement in enzyme production was obtained by scaling up the cultivation process to stirred tank bioreactor. Cultivations were carried out in 3 L stirred tank bioreactor, Bioflow III (New Brunswick, USA), at aeration rate of 1 vv m-1 and constant pH of 6.0. For batch cultures in bioreactor, both volumetric and specific productions were increased and the maximal volumetric enzyme production reached 3600 μkat L-1. Moreover, the cultivation in fed-batch culture with intermittent addition of soluble starch increased the enzyme production significantly reaching about 5300 μkat L-1 after 34 h.