Aflatoxins are toxins produced by the fungus Aspergillus. In addition to being acutely toxic, they are also known to be carcinogenic, so their inspection in foods is necessary1). Up to now, aflatoxin B1 is the only aflatoxin that has been regulated in Japan. However, beginning October 2011, the restriction extends to the total of aflatoxin B1, B2, G1 and G2.2). Here, we introduce two cases of analysis of these 4 aflatoxins (B1, B2, G1, G2), using the Prominence RF-20AXS high-sensitivity fluorescence detector, first by fluorescence detection using trifluoroacetic acid derivatization, and then direct detection without TFA derivatization.