  This paper is devoted to the study of the weak-strong uniqueness property for
the full compressible magnetohydrodynamics flows. The governing equations for
magnetohydrodynamic flows are expressed by the full Navier-Stokes system for
compressible fluids enhanced by forces due to the presence of the magnetic
field as well as the gravity and with an additional equation which describes
the evolution of the magnetic field. Using relative entropy inequality, we
prove that a weak solution coincides with the strong solution, emanating from
the same initial data, as long as the latter exists.
