The optical and charge transport properties of 1,2,4,5-tetrakis(5-methylthiophen-2yl)benzene (TMTB), electron donating and withdrawing groups substituted anthra-[1,2-b:4,3-b′:5,6-b″:8,7-b‴]tetrathiophene (ATT) molecules have been studied. The ground and excited states geometry was optimized using the density functional theory (DFT) and time-dependent DFT methods. The absorption and emission spectra were calculated at TD-B3LYP/6-311G(d,p) level of theory. It has been observed that the effect of solvent and the substitution of functional groups on the calculated absorption and emission spectra of ATT molecules is negligible. The charge transfer integral, site energy and reorganization energy for hole and electron transport in ATT molecules have been calculated. Molecular dynamics simulations were performed to find the most favorable conformation. The calculated charge transport properties show that the rate of charge transfer strongly depends on π-stacking angle and the studied molecules can be used as an organic semiconductor.