Kojic acid at the levels of 0.01, 0.1, and 1.0% (w/v) was incorporated in the growth media of Aspergillus flavus. In the presence of 0.01% of kojic acid, isolates I, II, and III produced 157, 113, and 135% aflatoxin, respectively, as compared to the control. At the highest level of kojic acid, i.e. 1%, aflatoxin production was inhibited to 74% in isolate I, but was little affected in isolate II (104%) and strongly inhibited in isolate III (54%). Kojic acid, at a concentration of 0.1%, was still stimulatory to isolate II, while it was inhibitory to isolates I and III. The dry weight of mycelia of the three isolates was not affected by kojic acid addition.