Alk. amylase-producing strains which had potential values in the industry were obtained.Five amylase-producing strains were selected from soils.The optimal composition of the medium was determined by the orthogonal test.The fermentation conditions were also initially identified in the shake flask fermentationThe strain named S II-6, which was isolated from the grasslands soils, had the highest amylase-producing activity when it was cultured for 8 h.The optimal fermentation medium with pH 9.0 was composed of 3% corn flour, 0.8% peptone, 0.6% disodium hydrogen phosphate, 0.2% ammonium sulfate and 0.15% ammonium chloride.After cultivated for 8 h in shaker at 40°C with 180 r/min, the amylase-producing activity of S II-6 reached 2114 U/mL.Five amylase-producing strains can be screened out, in which the strain S II-6 is an alk.-resistant α-amylase-producing strain.