Fig leaves were extracted with methanol and then fractionated with ethyl acetate and various buffers to get active fractions and determined the antimicrobial activities. The acidic and phenolic fractions fractionated from the methanol extract of fig leaves showed the strong antimicrobial .activities, but the basic and neutral fractions did not show any activities. The degree of antimicrobial activities of pheonlic fraction against: tested bacteria was higher than those of acidic fraction, but these against yeasts and mold were almost equivalent to those of acidic fraction. Especially, phenolic fraction was mostly affected on Staphylococcus aureus and Pseudomonas aeruginosa. Four antimicrobial substances purified from the phenolic fraction which showed the strongest antimicrobial activities among the fractions from fig leaves, were identified as psoralen(C_(11)H_6O₃, MW. 186), bergapten(C_(12)H_8O₄, MW. 216), β-sitosterol(C_(29)H_(50)O, MW. 414) and umbelliferone (C_9H_6O₃, MW. 162).