The Nile tilapia (Oreochromis niloticus), among cultivated species, obtained greater emphasis on farming for their sensory characteristics, good fillet yield, high productivity and hardiness, making it quite attractive in the whole country. This study aimed to determine and monitoring the biogenic amines in fillets of Nile tilapia (Oreochromis niloticus) cooled, packaged in modified atmosphere and irradiated during the storage. After obtaining samples, the tilapia fillets were divided into four different treatments: aerobic packaging (T1), modified atmosphere packaging (MAP) with 40/60 CO2/N 2 (T2), aerobic packaging and irradiation dose of 1.5 kGy (T3) MAP and irradiation using the same conditions and irradiation atmosphere (T4). The samples were kept at 0 ± 1 ° C for 14 days. The determination and monitoring of biogenic amines was performed after extraction, derivatization and analysis by high performance liquid chromatography. Regarding the appearance of biogenic amines, the modified atmosphere packaging (T2) showed positive effects in delaying the onset of biogenic amines. However, irradiation (T3) and MAP associated with irradiation (T4) obtained the best results when compared with only the MAP (T2) or packaged in aerobiosis (T1). We conclude that the synergistic effect expected in the use of irradiation associated with modified atmosphere packaging was not observed, the largest inhibitory effect on the formation of biogenic amines attributed to the use of irradiation.