Organochlorine pesticides, such as HCH (Hexachlorocyclohexane) and DDT (dichloro diphenyl tricolor ethane) and their metabolites were analysed in commercially important fishes, collected from fish (Cairo Nasr City, Obour Market, Suez Canal Area, General Market in Menoufia). In total HCH, the alpha isomer was recorded at very high level when compared
with other isomers. Similarly was the dominant metabolic compound in total DDT in all the fish species. The residual concentration of the pesticides in fishes was well below the tolerance limits prescribed in this study, the levels of organochlorine (gamma-BCH, AlphaBCH, Aldrin, o, and p'-DDE, endosulfan, dieldrin, p, p'- DDT, lindane, p, p'-DDD, o,
p'-DDD and methoxychlor) pesticide residues were investigated using fish samples. Five fish species (Oreochromis Niloticus, Siluriformes, Mugil cephalus, Bagrus bajad and Alces piscis) were collected for this analysis. Fish samples of similar size were collected in order to avoid possible error due to size differences.The fish samples were labeled with unique identification number. Samples of fishes were transported to the laboratory on the same day then it were dissected to remove the flesh of each species of fish and stored pending extraction and analysis. The extractions, clean up and de-fattening of the fishes' organs were carried out using standard procedures. Endrin was the most abundant pesticide residue in the tissues of all the examined fish species. The present study revealed also that in all the examined fish samples all the pesticide residues were above the maximum residue limits (MRLs) and dietary intake (ADI) that is why it could be an important source of transferring pesticides to humans