Two different agro residues were screened for alpha- amylase production using the Gram positive rod, Bacillus subtilis. Supplementation with different nitrogen and carbon source favoured the increased enzyme yield by submerged fermentation. Maximum enzyme yield titre was expressed as units as per micro mole of glucose yields. The objective of this study is to select a suitable strain for the production of amylase, screening of different agricultural by products as substrates for maximum enzyme production, application of different combinations of these substrates for enzyme production and optimization of cultural conditions for the production of amylase. Enzyme yield of Wheat bran and Rice bran were 51.04 ± 0.54 IU/g and 12.42 ± 0.15 IU/g respectively at the time of 40hr incubation at 37°C of which the wheat bran (WB) was proved as the best substrate source.