The larvae of the black soldier fly ( L., BSFL) have received increased industrial interest as a novel protein source for food and feed. Previous research has found that insects, including BSFL, are capable of metabolically converting aflatoxin B (AFB), but recovery of total AFB is less than 20% when accounting for its conversion to most known metabolites. The aim of this study was to examine the conversion of AFB by S9 extracts of BSFL reared on substrates with or without AFB. Liver S9 of Aroclor-induced rats was used as a reference. To investigate whether cytochrome P450 enzymes are involved in the conversion of AFB, the inhibitor piperonyl butoxide (PBO) was tested in a number of treatments. The results showed that approximately 60% of AFB was converted to aflatoxicol and aflatoxin P. The remaining 40% of AFB was not converted. Cytochrome P450s were indeed responsible for metabolic conversion of AFB into AFP, and a cytoplasmic reductase was most likely responsible for conversion of AFB into aflatoxicol.