The aqueous alcohol extract of the leaves of Alibertia macrophylla afforded two epimeric pairs of iridoid aglycones and one of them showed high inhibitory activity against Aspergillus niger, Ciadosporium sphaerospermum, C. cladosporioides and Colletotrichum gloesporioides. Three of the compounds are reported for the !irst time from natural sources. Their structures were established on the basis of spectroscopic studies, mainly through 13C NMR analysis.