Increasing surface and groundwater pollution is a major problem due to ever-increasing population growth, industrialization, proliferation of microorganisms, and intensive agricultural practices causing a shortage of potable water. Due to this problem, more attention has to be paid to wastewater recycling. Traditional wastewater treatment technologies can be expensive and sometimes have low efficiency. Hence, there is the utmost requirement to continuously evaluate innovative technologies that complement and improve these traditional wastewater treatment processes to solve these problems. Methods based on exploiting nanomaterials are among the major focuses of improving wastewater management. The chapter emphasizes the potential of various nanomaterials in treating wastewater. The underlying mechanisms have been explored in detail with the help of specific examples. The toxicity and ecological impact of nanomaterials have been discussed along with their future prospective for sustainable and safe water management.