Thirty-seven accessions of oilseed sunflower were evaluated under natural field conditions for growthperformance, ligno-cellulosic mass production of bioenergy, and metal uptake potential during theremediation of arsenic and mercury-contaminated soil. Significant variations were observed in the lignocellulosiccomponents of plant stems at maturity, decreasing the following order: totalsugars > cellulose > hemicellulose > lignin > ash. A significant difference was also noted in metal uptakeamong the different accessions. The highest concentrations in the above-ground parts were 14.08 and0.40 mg/kg, respectively for As and Hg. In rhizosphere soil concentrations of inorganic As species(arsenate: 69.73 mg/kg, arsenite: 4.41 mg/kg) were higher, as compared organic As (dimethyl arsenic:0.22 mg/kg); mono-methyl arsenic: 0.02 mg/kg). Arsenate concentration (3.72 mg/kg) was higher in root,whereas arsenite concentration (0.47 mg/kg) was higher in the shoots. Many accessions showed good oilproduction (26e45.6%), with the highest percentage of oleic (75%) and linoleic acids (37.6%). These resultssuggest that some oilseed sunflower cultivars could be adopted as crop plants for effective remediationof lightly to moderately As-/Hg-contaminated soils, coupled with agro-production.© 2020 Published by Elsevier Ltd.