A grand total of 21 samples of fresh fish fillets (Oreochromis niloticus) were collected randomly from different fish markets in Benha, Kalyobia governorate to determine the effect of some essential oils"clove oil(1%), thyme oil (1%) and lemon oil"(1%) at4C for 2and 4 days on their contents of various biogenic amines "histamine, putrescine, cadaverine and tyramine". The results indicated that histamine levels in the examined fish fillets were reduced by 5.5% - 14.75% by addition of clove oil (1%), 7.25 - 20.0% by addition of thyme oil (1%) and 15.8% - 29.3% by addition of lemon oil (1%) after 2 and 4 days, respectively. While, addition of clove oil (1%), thyme oil (1%) and lemon oil (1%) cause reduction toputrescine by 9.6 - 11.9%, 12.5 - 16.4% and 19.35% - 34.1% after 2 and 4 days, respectively. Concerning to cadaverine levels, the reduction occurred by 7.7 – 9.3%, 10.4 – 22.9% and 15.8% - 29.8% after 2 and 4 days, respectively. Finally, addition of clove oil (1%), thyme oil (1%) and lemon oil (1%) cause reduction totyramine by 5.2 – 10.6%, 16.5 - 16.3% and 22.4% - 25.1% after 2 and 4 days, respectively. The obtained results it allow concluding that the addition of essential oils lead to reduction of biogenic amines in fish fillets eliminating the hazard effect of biogenic amines on human