The concentrations of iron, lead, cadmium, copper, manganese, mercury and arsenic were measured in water, sediment, five macrophytes (Typha angustifolia, Iris pseudacorus, Polygonum amphybium, Myriophyllum spicatum and Lemna gibba) and five fish species (Sander lucioperca, Abramis brama, Carassius gibelio, Silurus glanis and Arystichtys nobilis) in the Gruža Reservoir, used for water supply and recreational fishing. The concentrations of all examined elements were higher in sediment than in water. The values of the ratio between element concentrations in the sediment and those in the water were the highest for Fe and As. Among the five plant species, the highest concentrations of Pb and Mn were observed in T. angustifolia, while the highest concentrations of Fe, Cu and Hg were in L. gibba. I. pseudacorus and P. amphybium had the highest concentrations of Cd and As, respectively. Among the fish species, C. gibelio showed the highest tendency of element accumulation (Fe, Cd, Cu), followed by S. lucioperca (Pb, Hg), A. brama (Mn) and A. nobilis (As). The average concentrations of elements in fish muscle, except for As in A. nobilis (2.635 ± 0.241 mg kg(-1) ww), were below the limits that are considered safe for human consumption in accordance with the European Commission Regulation and Official Gazette of Serbia.