Abstract: High-performance electromagnetic wave absorbing materials (EWAMs) are expected to solve electromagnetic wave radiation problems in both the military and civil fields. The desired features of EWAMs include strong absorption over a broad bandwidth, low density, thinness, oxidation resistance, wear resistance, ability to withstand high-temperatures and high strength. Carbon-based materials, including nanostructures and composites, are attractive alternatives to EWAMs because of their unique structures and properties. We summarize recent achievements in carbon-based EWAMs, including different dimensional (0D, 1D, 2D and 3D) carbon nanostructures and various types of carbon composites (dielectric/carbon, magnetic/carbon) and hybrids. The factors affecting the absorption of electromagnetic microwaves include electrical conductivity (σ), permittivity (ε) and permeability (μ) are discussed based on the electromagnetic microwave absorption mechanisms. Representative carbon-based EWAMs and the corresponding mechanisms of improving their electromagnetic microwave absorption are highlighted and analyzed. Strategies for the modification of carbon-based EWAMs are summarized and research trends are proposed.