This study aims to investigate the heavy metals concentrations in muscles of three raw fish species; mullet (Mugil cephalus), Nile tilapia (Oreochromis niloticus) and catfish (Clarias gariepinus) obtained from four different locations; the Nile River and Lakes of Wadi El-Rayan, Edku and Burullus during July 2019, and to study the effect of common grilling technique on their concentration in Nile tilapia samples as abundant fish. 17 elements were determined in fish muscles by ICP-OES Agilent 5100 VDV. Results revealed that the concentrations of heavy metals in fish species based on location were taken the following order; Burullus ˃ Nile River ˃ Wadi El-Rayan ˃ Edku. Whereas they were tilapia ˃ catfish ˃ mullet of Nile River, mullet ˃ tilapia ˃ catfish of Wadi El-Rayan, catfish ˃ tilapia ˃ mullet of Edku and catfish ˃ tilapia ˃ mullet fish of Burullus. The grilling process reduced the heaviest metals concentrations in tilapia species compared to raw samples. In conclusion, the heaviest metals in the muscles of fish species were lower than the maximum permissible limits set by International and Egyptian Standard Specifications and Legislations of food. Also, the grilling technique is an appropriate method to reduce the harmful effect of some heavy metals.