The invention adopts addition of graphene to toughen boron carbide ceramic. The mechanism of the graphene reinforcing and toughening is crack deflection, branch, bridge connection, fracture, pulling out and the like. Different from the one-dimensional toughening of fibers, nanotubes, whiskers and the like which are aggregated easily in the past, the graphene is a two-dimensional material, can significantly reduce the mutual attraction among graphene sheets to avoid agglomeration through surface modification and decoration, and has very good dispersity and stability in some liquid mediums. Forexample, the surface of oxidized graphene contains a large amount of oxygen-containing functional groups such as hydroxide radicals, carboxyl and the like, and a stable and disperse graphene solutioncan be prepared; the graphene solution is mixed with ceramic matrix slurry, a graphene ceramic mixed raw material with a good implantation effect can be obtained, therefore, the reinforcing and toughening effects of the graphene ceramic mixed raw material are relatively stable, and the technological feasibility is better.