Abstract:The amylase -producing strains were isolated from soil. After initially screening by starch culture medium， the DNS method was used to determine the total enzyme activity and α-amylase activity of the crude enzyme solution by fermentation extraction. The screened strains were identified through morphological observa－ tion and physiological and biochemical reactions. Results showed that： four strains of amylase-producing Bacil－ lus were isolated. The ratio of hydrolysis zone diameter to colony diameter was 1.7-3.5. Two strains of them had high amylase-producing activity， which the total enzyme activity reached 19.760 U/mL and 15.432 U/mL. The α-amylase activity of four strains of Bacillus was 6.4 U/mL～10.4 U/mL. The four strains of Bacillus were authen－ ticated that one was Bacillus subtilis， the other three were Bacillus cereus. The ability to produce amylase of Bacillus subtilis was superior to Bacillus cereus.