Pure water is the major leading issue nowadays and is the concerned status for wastewater treatment via a variety of techniques. Various toxic substances including heavy metals, hydrocarbons, pesticides and chemicals have a negative impact either directly or indirectly on both biotic and abiotic components. Sometimes it may also show carcinogenic effects on human beings; thus, their removal must be the interest of researchers. To minimize the risk of harmful effects of such hazardous substances, nanomaterials could be one of the options for wastewater management. Nanoparticles can be categorized into different groups: metal oxide, silver-, iron-, cellulose- and carbon-based nanoparticles. Silver-based nanoparticles have antimicrobial activity and are widely used to overcome problems related to the organic material. Metallic oxide has promising potential to remove heavy metals including copper, nickel, chromium and zinc easily. Nanoadsorbents such as hematite, magnetite and maghemite have antimicrobial activity; hence, they are widely used for the decontamination of water. Nanotechnology has been emerging as a powerful weapon in the advancement of industries and agricultural fields. Carbon nanotubes (CNTs) are more effective than activated carbon as they interact with pollutants. Membranes are typically utilized to reduce impurities from water such as bacteria, viruses and other microbes. This chapter highlights the potential of nanomaterials for wastewater treatment. Nanotechnology could be considered an eco-friendly approach for wastewater management. Thus, nanomaterial-based research is ongoing to minimize the risk of pollutants in an eco-friendly manner.