Water pollution has raised the alarms toward the maintenance of life on earth. Industrial revolution has given a big blow to the aquatic health of the planet. Treatment of wastewater is one of the foremost issues being considered by the scientific community. Carbon-based nanomaterials have grabbed the interest of the research community owing to their noteworthy characteristics. These nanomaterials include carbon nanotubes, graphene, graphene oxide, reduced graphene oxide. Graphene-based nanomaterials are found to have different roles in wastewater treatment via processes like adsorption, catalysis, and membrane filtration owing to their remarkable properties and the different mechanisms associated with their activity. This chapter provides a useful insight into the various roles and the factors associated with the appliance of graphene-based nanomaterials for wastewater treatment along with their pros and cons—a future-looking perspective.