A high-yield Kojic acid producing mutation UC6-90 which do not produce aflatoxin was obtained from Aspergillus oryzae 2336 by UV and 60Co ray mutation techniques with quick screening method. The yield of Kojic acid increased from original 2.34 g/L to 50.47 g/L using corn starch as a carbon source after 7 days.This strain can beapplied in industrial scale production using genetic stability experiment.