In this investigation, α-amylase gene region from a thermophilic Bacillus stearothermophilus isolated from sugar beet juice obtained from Dakahlia Sugar factory (Egypt) was cloned to competent Bacillus licheniformis ATCC 27811 cells. The original and modified Bacillus strains were spread on different media composition and enzyme activity was determined. According to the results, the α-amylase enzyme was seen to have highest activity at media containing sugarcane bagasse and/or sugar beet pulp. The results revealed that modified Bacillus surpassed the original one at all studied media. This obtained result proofed that gene transferred into BL had effective action on increase α-amylase activity. The thermo-stability studies revealed that enzyme activity of modified bacillus was high for the first 8 hours at 90°C, it was ranged from 95-90 % after 6 hours (enzyme activity decreased from 7.80 to 7.02 gm glucose/ml) then, decreased to 65-63 % at the end of 24 hours.