Addition of cooper-monovalent-nicotinic acid complex to a synthetic medium specific for kojic acid production by Aspergillus flavus enhanced the production by about 47%. The substance is proposed to act via a biochemical utilization of the copper(I)-B3 complex in a manner similar to that of the naturally utilized nicotinic acid. NAD and NADP like carriers with higher reactivity have been predicted. According to this prediction the biosynthetic route of kojic acid has been interpreted on the basis of a model proposed by Bajpai et al. (1981). In this model the enzymes participating are dependent on NAD and NADP (glucose dehydrogenase and gluconate dehydrogenase) as well as on other reduction processes.