The increasing requirement for ever newer and more efficient materials used to cleanse highly polluted waters brought carbon nanostructure-doped hydrogels into prominence as new remediation tools. Hydrogel matrices contain dispersed carbon nanostructures like carbon nanotubes, carbon dots, graphene, and fullerene to equip and improve their physicochemical properties. Hybrid materials have shown great adsorption capacities, surface areas, good mechanical strength, and enhanced chemical stability, and hence, they are suitable for the removal of various heavy metals, dyes, and organic contaminants from wastewater. This chapter outlines a thorough overview of properties and synthesis routes of carbon nanostructures and hydrogels, followed by a detailed discussion of the fabrication methods of carbon nanostructure-doped hydrogels. Improved contaminant removal efficiency will be evaluated based on recent advances and real-world opportunities in wastewater treatment. The chapter will also discuss the challenges that need to be overcome for scalable adoption, regeneration, environmental impact, and cost-effectiveness.