The thermodynamics of a fcc hard spheres solid is accurately described by recent density-functional approximations. This state is used as a reference in a thermodynamic perturbation analysis for a density-functional theory of Lennard-Jones solids. The free energy functional incorporates liquid state structural information and a density dependent potential decomposition for the Lennard-Jones interatomic potential. The computed free energies of the solids compare very well with the predictions of atonlistic simulations. Solid-liquid coexistence is predicted consistently to within 15% of results of Monte Carlo simulations, over the temperature range 0.75 ≤ kT/c ε ≤ 10.