Streptomyces minoensis DMCJ-144 isolated from soil produces the ${alpha}-amylase$ inhibitor. Optimum culture conditions for ${alpha}-amylase$ inhibitor production of the strain were determined in this experiment. The optimum composition of the culture medium was studied by supplementing various carbon sources, nitrogen sources, vitamins, and metal salts to the basal medium containing 1% glucose, 0.1% asparagine, 0.005% $MgSO_4{cdot}7H_2O$, 0.005% $K_2HPO_4$, 0.005% NaCl. Other culture conditions such as the culture temperature, initial pH of the medium, aeration, and culture time were also investigated. When the strain was cultured in a 100 ml flask containing 20 ml of 2% glucose, 0.5% beef extract, 0.0002% riboflavin, 0.0002% thiamine HCI, 0.01% $ZnCl_2$, 0.005% $MgSO_4{cdot}7H_2O$, 0.005% $CuSO_4{cdot}5H_2O$, 0.005% NaCl, pH 7.2, 180 rpm at $30^{circ}C$, the maximum production of the ${alpha}-amylase$ inhibitor was observed after 5 days of the cultivation.