There has been an emerging trend in using nanotechnology to transform modern-day technology completely. Advanced nanomaterials are greatly used in engineering applications, including environmental remediation, due to their excellent performance properties like high surface area, which always results in high performance efficiencies. The global environment is exposed to various types of pollution, including air, soil, and water, due to modernization and urbanization driven by industrialization. As a result, it is critical to explore novel technology to help address the problem of environmental contamination. Nano-remediation is a growing approach that uses an engineered material to clean and restore contaminated environments. This technology is a fast, efficient, and effective approach for handling persistent substances, such as heavy metals, pathogens, pesticides, halogenated chemicals, and chlorinated solvents. However, the traditional techniques of producing nanoparticles present dangerous environmental risks. To address these issues, scientists have shifted their attention to the more beneficial green synthesis approach, which is both cost-effective and environmentally friendly as it does not require any hazardous precursors or demanding processing conditions. Nanoparticles have great potential in water/wastewater treatments and environmental pollution control. This chapter is focused on some possible green synthesis and applications of nanomaterials for environmental remediation, challenges, and solutions.