The dissociation energies for S-H bonds in thiols and thiophenols and C-H bonds in cyclic thiohydropyrans and thiooxalanes were calculated from kinetic data in terms of the parabolic model of radical reactions. Thermochemical data on sulfur organic compounds were analyzed; the strengths of the C-C, C-S, S-S, C-H, and S-H bonds were estimated; and the enthalpies of formation of sulfur-contaming radicals were determined. The activation energy for radical abstraction reactions in the sulfur-containing compounds was estimated.