The accumulation of some heavy metals such as Pb, Cd, Cu and Ni was determined in water, sediment and fish samples (Albumus escherichii, Cyprinus carpio and Silurus glanis) collected from Nallihan Bird Paradise (NBP) and its vicinity (Sariyar Dam). The results showed that these metals are found widespread throughout the study area, but metal concentrations in the water samples are below the detection limits (BDL). Pb, Cd, Cu and Ni contamination were determined in sediments and in fish tissues (muscle and liver) and it was seen that they were accumulated and biologically magnified in fish tissues. Metal concentration levels in sediment samples were higher than that of water and fish tissues. The highest amount of metal concentrations in sediment samples among seven stations were determined in Usakbuku (Pb: 0, 49 ppm), Sakarya River (Cu: 1.12 ppm) and Sariyar (Ni: 0.77 ppm). Unlikely to the other stations, no metal residues were determined in the sediment samples of Aladag Creek Station.