A total of one hundred and twenty fresh fish samples were randomely collected from Giza and Cairo markets (60 of each; 20 of Tilapis nilotica, Mugil cephalus and Bagrus bayed) ‘to estimate the concentration of Mercury(Hg) , lead(Pb) , cadmium(Cd), and zinc(Zn). Residues in flesh of the above mentioned fresh water fishes were estimated by using Atomic Absorption Spectrophotometer (AAS). The obtained results indicated that the mean valuestS.E of Hg in examined Tilapia nilotica, Mugil cephalus and Bagrus bayed were (2.2+40.26 and = 2.1+0.92, 2.0140.71 and = 1.1+0.88, 0.115+0.015 and 0.021+0.042 ppm) in Giza and Cairo Governorates respectively .Also Pb residues were (1.015+0.5 and 1.1+0.84, 1.840.61 and 1941.01, 1.1240 .13 and 0.32140.14 ppm) respectively. While the Cd values were (0.85+0.1 1 and 1.09+40.416, 3.1£0.72 and 240.92 , 2.51+1.51 and 0.62+0.32 ppm) respectively. Concerning Zn values, they were (12.7241.21 and 10,240.51, 12.0541.15 and 10.7£0.63, 11.0240.5 and 10.86£0.119 ppm) respectively. The obtained data were evaluated according to the permissible limits of FAO/WHO (1992) and E.S.S No.2360 issued by Egyptian Organization for Standardization and Quality Control (EOSQC) (1993). The public health significance and suggested precautions for minimizing the level of such heavy metals in food were discussed.