Abstract: Bacillus megaterium isolated from leaves of Avicennia marina (Forssk.) was screened for their ability to produce α-amylase, studied in submerged fermentation by using an Adlof-Kuhner orbital shaker. The levels of amylase production detected in culture supernatants varied greatly with the type of carbon source used such as starch, lactose and glucose. Effect of different nitrogen sources revealed that peptone increase the enzyme yield. The enzyme activity increased between 1.5 and 3 g L-1 of yeast extract concentration and optimal concentration of peptone for the production of amylase was detected as 6 g L-1. The maximum enzyme activity was obtained under optimum conditions of an incubation period of 72 h, an incubation temperature of 35°C and pH of 6.5.