To evaluate aquatic macrophyte species, an indicator organism of heavy-metal pollution in bio-monitoring studies of the aquatic ecosystem is studied. The aim of this study is determining some heavy-metal (Pb, Cr, Cu, Mn, Ni, Zn, and Cd) accumulation of aquatic plants in the lower Sakarya river basin which is located in northwestern Turkey. This study is performed by collecting aquatic plants from the research area (Poyrazlar Lake, Taskisigi Lake, Sapanca Lake, and Acarlar Longoz) between December 2012 and 2013. After the solution process of the plants is performed, Pb, Cr, Cu, Mn, Ni, Zn, and Cd amounts are determined by ICP-OES device. The determination of seven elements in the samples was performed by ICP-OES. The experimental results comply with the reported values in the literature. According to the analysis, heavy-metal concentration of the plants in the Sakarya river basin is between the range of Cu 2.0 +/- 0.1-30.0 +/- 0.8 mu g/g, Mn 2.3 +/- 0.2-12.5 +/- 0.8 mu g/ g, Ni 0-2.5 +/- 0.3 mu g/g, and Zn 12 +/- 0.2-800 +/- 0.8 mu g/g. Pb, Cr, and Cd amounts could be detected. Regional accumulations are interpreted by identifying pollution maps for each metal.