Interest in conductive organic polymers has considerably increased since the discovery in 1977 of the doped molecule polyacetylene. Recently, polymers of dithienopyrrole (DP), dithienothiophene (DT) and thionaphtheneindole (TNI) have been synthesized electrochemically showing for several monomer ratios good electrochromic and conducting characteristics. The aim of this paper is to investigate theoretically the electrical and optical properties of the above mentioned polymers. Therefore, we have performed a conformational structure study followed by electronic structure calculations. Also we present a spectroscopic study for oligomers built with the monomers of these materials. In our calculations we utilized the semiempirical method AM1 for the electronic and geometric simulation of the polymers. Optical absorption spectra for neutral and charged systems were calculated using the INDO/S-CI method. All three systems showed similar electronic behavior but significant differences can be seen on the TNI monomer optical spectra. Our results are in good agreement with the experimental ones.79354359