To find ${alpha}-amylase$ inhibitors produced by microorganisms from soil, a strain which had a strong inhibitory activity against bacterial ${alpha}-amylase$ was isolated from the soil sample collected in Korea. The morphological and physiological characteristics of this strain on several media and its utilization of carbon sources showed that it was one of Streptomyces species according to the International Streptomyces Project method. The amylase inhibitor of this strain was purified by active carbon adsorption, silicagel column chromatography, SP-Sephadex C-25 column chromatography, adsorption on Amberlite XAD-2. The inhibitor was oligosaccharide which was composed of glucose. The inhibitor had inhibitory activity against other amylase such as salivary ${alpha}-amylase$, pancreatic ${alpha}-amylase$, fungal ${alpha}-amylase$ and gluco-amylase.