Significant characteristics of electron structure ionization potential (IP) and electron affinity (EA), and then they are the parameters characterizing of donor-acceptor properties of petroleum resins and asphaltens are calculated. Energy of the highest occupied molecular orbital (the HOMO), E LUMO is the energy of the lowest unoccupied orbital (the LUMO) have been calculated of quantum chemistry method ab initio RHF/3-21G**. The ionization energies and electron affinity of asphalt-resins substances (ARS) model fragments was estimated on the empirical equation. The Suppositions were confirmed, that of polycyclic free radical fragments ARS are organic semiconductor.