In this study, the screening of α-amylase producing strains from endophytic bacteria in Siraitia grosvenorii and surrounding soil were preformed, and the optimum fermentation conditions for α-amylase producing strains were performed. Our results showed that 15 strains were isolated from the Siraitia grosvenori and 8 strains from surrounding soil. High amylase producing strains 2-1 (surrounding soil) and R-4 (root endophytic bacteria) were isolated. The identification results showed that 2-1 strain was staphylococcus and R-4 strain was bacillus, which were gram positive bacteria. The appropriate condition of enzyme production for strains 2-1 and R-4 were determined. For strain 2-1, the appropriate conditions were 1.0% ammonium chloride, 0.5% yeast powder, 1.0% soluble starch, 0.4% sodium chloride, fermentation temperature 40℃, and fermentation time 3 days and the enzyme production was 127.65U/mL under these conditions. For strain R-4, the appropriate conditions were 0.5% yeast powder, 1.0% ammonium chloride, 0.05% sodium chloride, 2.0% soluble starch, fermentation temperature 40℃, and fermentation time 3 days, and the enzyme production was 197.21U/mL under these conditions.