Abstarct: The Badavar River located in Lorestan province is an important water supply for livestock and farming purposes. A part of the river passes through residential areas (Noor Abad city), and receives various urban and domestic wastewaters. The aim of this study is to assess the quality of water and sediments of the Badavar River, and to study the factors influencing the river quality. For these purposes, 19 water samples (for major ion concentration, potentially toxic elements content and microbial pollution) and 5 sediment samples (for major and trace element analysis) were collected and analyzed using standard methods. On the basis of the hydrochemical investigations, the water samples are Na-HCO3 type. The obtained results indicates that the water quality is influenced by halite and gypsum dissolution, calcite and dolomite precipitation, and ion exchange processes. The concentration of the major ions is influenced by Gypsum, halite dissolution, calcite and dolomite precipitation ion exchange and wastewater-irrigation runoff entering the river. On the basis of sodium adsorption ratio, permeability index, magnesium hazard index, as well as the Wilcox plot, all water samples are suitable for agricultural usage. However, the water samples are not suitable for agricultural usage on the basis of sodium content and total hardness. The obtained results show that in some stations, the Badavar River is microbially contaminated. The concentrations of potentially toxic elements (except for Pb) in the studied samples are lower than the FAO (Food and Agriculture Organization of the United Nations) standards. The concentrations of Cr, Cu, Zn and Mn in all samples and the concentration of Cd, Co, Ni, Pb and Se in some water samples are higher than their content in the average freshwater composition. The sediments of the Badavar River are contaminated with respect to Cd، Cr and Ni compared with the world standards. The enrichment factor values shows that Cd and Cr are from anthropogenic sources. The distribution coefficient shows the highest mobility for Cu and Pb, and the lowest mobility for Ni. The obtained results in the present study confirm the necessity of wastewater disposal management in the study area.