The effects of aqueous extract of fresh garlic (Allium sativum) bulbs on the growth of a large number of fungi are presented. While many of the test species did not grow as well in the presence of the garlic extracts, others were not affected and a few were stimulated. Some important wood-rotting species, particularly filamentous Basidiomycetes, were inhibited. Histoplasma capsulatum was killed by the extract. Sporulation of Mucor plumbeus and Penicillium claviforme was enhanced by the extract. Autoclaving the extract usually removed the inhibition.