The amylase-producing bacteria were isolated and screened from the old liquor of Dadian, and the retort was used to perform the preliminary screening by the iodine fumigation method. The amylase activity was measured by rescreening, combined with colony morphology observation, 16S rDNA homologous sequence analysis, and physiological and biochemical screening. The high-yield amylase bacteria were identified to study the single factors affecting the ability of the bacteria to produce amylase, including carbon sources, fermentation time, initial pH and inoculum size, and the optimal enzyme production conditions were determined by response surface optimization. The results showed that strains 6-10 were Bacillus velezensis. The optimal conditions for enzyme production were determined by response surface optimization i.e. fermentation for 4 d, initial pH value at 5, and inoculum size at 10%. After optimization, the enzyme production capacity reached (164.37±3.25) U/mL, which increased by 4.43 times.