Ethanol extracts of puchiin were assayed for its antimicrobial properities. The result showed puchiin extracts had antibacterial activities. Futhur more, it was revealed that puchiin extracts had strong anti-microbial activity against bacterial tested under the condition pH 7. Minimum inhibitory concentration value of extracts to Staphylococcus aureus, Escherichia coli and Bacillus subtilis was 0.63, 1.25, 1.25 g/L respectively, which was stronger than molds and budding fungus was weaker than that that of potassium sorbate. Antimicrobial activity against of potassium sorbate.