The antifungal activity of essential oils (EO) of peppermint (Mentha piperita), clove (Syzygium aromaticum), rosmary (Rosmarinus officinalis), anise (Pinpinella anisum), fenugreek (Terigonella foenum-graecum), Thymus (Thymus vulgaris), black mustard (Brassica nigra) and fennel (Foeniculum vulgare) was evaluated in vitro against Aspergillus flavus  growth and aflatoxins production. The effect of different concentrations of essential oils on A. flavus and aflatoxin production was determined. At levels of plant Eo  (0.4, 0.6 and 0.8%) , results indicated that there were no inhibition effect on the growth of A. flavus, except metha piperita oil. The Eo of mint at all assayed concentrations (0.6. 0.8 and 0.1%) showed strongly inhibition effect on the production of aflatoxins B₁, B₂, G₁ and G₂. GC/MS was used to identify the main components of the oils  under investigation. High amount of menthol in the Mentha piperita Eo showed strongly antifungal activity. The level of aflatoxin B₁ production was 0.0 ppb for the samples treated with the mint oil and synthesis menthol at concentrations of 0.6 and 0.8%.