Abstract:In order to research the antibacterial activity of beta-glucan，polyphenols and flavonoids in oat，this paper used oats as raw materials，to extract the beta-glucan，polyphenols，and flavonoids，Escherichia coli，Bacillus subtilis，Ester-producing yeast and Aspergillus Niger were used as tested strains，filtering paper method and Oxford-cup tests was used to study the bacteriostatic effect of each substance on the four strains.The two methods results showed that oat beta-glucan，polyphenols and flavonoids had a certain inhibitory effect on the above four tested strains，among which oat polyphenols had the strongest antibacterial activity，followed by flavonoids and beta-glucan，and its antibacterial ability was positively correlated with the concentration of active substances.The inhibitory effect of the three substances on the four tested strain was as follows：Escherichia coli＞Bacillus subtilis＞Ester-producing yeast＞Aspergillus Niger.This study showed that oat beta-glucan，polyphenols and flavonoids had certain antibacterial activity，which provided certain data support for the development and utilization of oat active ingredients in food antisepsis.