Nanoscale composite materials have an immense potential to cleanse wastewaters from multiple points of view, because of their higher surface potential and synthetic reactivity, peculiar mechanical quality, and cost-adequacy. This article focuses on the removal of highly harmful heavy metal ions, such as lead and mercury, using the efficient Nanocomposite adsorbent Graphene Oxide Silica [GO-Si], which was synthesized in this work. The effect of the initial pH of wastewater, its temperature, the dosage of adsorbent on the removal of lead as well as mercury was studied. Besides, the adsorption kinetics and mechanism on GO-Si composite were investigated. The greatest adsorption measure of lead and mercury on GO-Si achieved were 347.2 and 266 mg/g, respectively. The morphology studies of GO-Si showed the presence of a highly porous surface which makes GO-Si most effective in terms of adsorption. The TEM, SEM studies confirmed the presence of Silica on the surface of the composite. Regeneration of composite adsorbent makes it worthy for five more cycles. Thus, the outcome of this study depicts that the GO-Si can be employed to remove environmental pollutants such as lead and mercury at low cost. © RASĀYAN. All rights reserved.