Recently superconductivity in graphite-sulfur composites was experimentally observed. In this work we have analyzed the electronic structure changes associated with the presence of sulfur atoms in one and two dimensional graphite layers. We have considered ordered and disordered sulfur atoms distributions in many configurations. The density of states (DOS) of these structures were obtained using the negative factor counting (NFC) technique coupled to a tight-binding Hamiltonian (Hückel type). Our results indicate that the incorporation of sulfur atoms at edge graphite layers (changing their global geometric curvature and increasing the DOS at the Fermi level) might be in the origin of the graphite superconductivity.689 127132Da Silva, R.R., Tores, J.H.S., Kopelevich, Y., (2001) Phys. Rev. Lett., 87, pp. 147001-147011González, J., Guinea, F., Vozmediano, M.A.H., (2001) Phys. Rev. B, 63, p. 134421Nagamatsu, J., Nakagawa, N., Muranaka, T., Zenitani, Y., Akimitsu, J., (2001) Nature (London), 410, p. 63Dean, P., Martin, J.L., (1960) Proc. Roy. Soc., A259, p. 409Ladik, J., Seel, M., Otto, P., Bakhshi, A.K., (1986) Chem. Phys., 108, p. 203Galvão, D.S., Dos Santos, D.A., Laks, B., De Melo, C.P., Caldas, M.J., (1989) Phys. Rev. Lett., 63, p. 786Lavarda, F.C., Dos Santos, M.C., Galvão, D.S., Laks, B., (1994) Phys. Rev. Lett., 73, p. 1267Galvão, D.S., Laks, B., Da Silva, R.R., Torres, J.H.S., Kopelevich, Y., to be published