The additional effects of lauric acid as a carbon source on the growth of Aspergillus oryzae，Aspergillus ochraceus, Penicillium citrinum and Penicillium notatum were examined. Lauric acid has value as a carbon source of these four kinds of fungi on plate culture. But this acid has no value to the growth of Penicillium citrinum and P. notatum on the static liquidcultures. Fair inhibition effects oflauric acid were seen on the shaking liquid cultures of these organisms. Almost the perfect inhibitions of growth were seen on the anaerobic cultures of these organisms with carbon dioxide.