Five heavy metals namely, cadmium, copper, iron, lead, and zinc were determined in water and fish samples obtained from three different lakes and fishponds in Egypt over nine months to assess pollution with those toxic metals. Water and fish (Tilapia sp.) samples were collected from Abbassa fishpond, Lake Qaroun, and Wadi El-Rayan Lake. The results showed that concentrations of the five metals varied significantly among sites and seasons.