Carbon nanomaterials are widely used in the treatment of water pollutants because of their structural characteristics such as large specific surface area, , complex pore structure, , and rich surface functional groups. This paper summarized the carbon sources and preparation methods of nanocarbon materials, , analyzed the principles and influencing factors of nanostructure regulation of carbon materials, , reviewed the research progress in nanocarbon adsorption of toxic pollutants in water, , and put forward the bottlenecks that need to be broken through for the future industrial application of nanocarbon materials. Hydrothermal, , pyrolysis and chemical vapor deposition are the common methods for the preparation of nanocarbon, , and traditional carbon sources, , such as sugars, , petrochemicals, , and biomass, , can be used to obtain nanostructured carbon through the modulation of parameters such as preparation temperature and activator. Carbon nanotubes, , carbon nanospheres, , and nanoporous carbon have been developed for better contact with pollutants, , thus exhibiting significant adsorption advantages for toxic pollutants such as phenols, , benzenes, , dyes, , antibiotics, , and heavy metal ions. In order to realize the wide application of nanocarbon adsorbent materials, , further research is required to be carried out in the future on the development of green and efficient preparation process of nanocarbon, , the exploration of the formation and evolution law of carbon structures, , the design of macroscopic use scheme of nanocarbon, , and the development of nanocarbon based composite materials.