The environmental damage is caused by urbanization, industrialization, and population growth. These factors are responsible for the waste discharge into aquatic bodies leading to water pollution. To solve this problem, new, eco-friendly, affordable, and repeatable methods must be developed. Nanobiotechnology, which uses natural sources to biosynthesize nanomaterials (NMs), is showing great promise. The scientific literature has previously established conventional methods of remediation, such as reactive, adsorptive, ex situ, in situ, and open production of biogenic NMs. In this chapter, we have discussed the application of green-synthesized NMs and NPs in wastewater treatment, involving adsorption, photocatalysis, membrane filtration, disinfection of the material platforms, fabrication, the fate of NMs, and performance optimization of the NMs that are used in removing the contaminants of water. Additionally, the elimination of emerging contaminants during wastewater treatment has made efficient use of their low toxicity, availability, energy efficiency, adaptability, biodegradability, and biocompatibility properties.