Verticillium tricorpus utilized glucose, xylan, pectin and carboxymethylcellulose (CMC) as carbon sources in liquid culture, with most vapid growth on glucose or glucose plus CMC. Xylanase and polygalacturonase were produced on all carbon sources, but least on glucose. Endo-beta-Glucanase, Exo-beta-Glucanase and beta-Glucosidase were produced on all except glucose. Production of Exo-beta-Glucanase and beta-Glucosidase was maximal on pectin, followed by xylan, whereas Endo-beta-Glucanase production was highest on CMC. Maximum amounts of xylanase and polygalacturonase were produced on xylan and pectin, respectively Thus the production of these enzymes is influenced by different factors in each case.