Abstract:Background and Objectives: The thermal radiation of a graphene sheet is considered, as well as the power absorbed by the specified sheet per unit surface in the thermodynamic equilibrium with vacuum radiation. From the comparison of these values, correlation relations are established for fluctuations in the surface current density in graphene and in a 2D conductive sheet similar to it, described by surface conductivity. These relations should be used in the theory of dispersion interaction of structures with graphene, using the Rytov-Levin and Lifshitz method of introducing fluctuation sources into Maxwell's equations. Model and Methods: We consider the equilibrium of a graphene sheet with a Planck thermal field from the principle of detailed equilibrium. From this we get correlation relations. With their use, we obtain the density of thermal radiation. Results: The thermal radiation densities of a graphene sheet at different temperatures have been obtained, as well as the specific heat transfer between two graphene sheets at different temperatures. Conclusion: The obtained correlations may be used for calculations of dispersion forces.