Conformational analysis, dipole moment, HOMO-LUMO energy difference (Delta E) and polarizability of 3-(2-chlorophenyl)thiophene are studied using HF/6-31++G** and B3LYP/6-31++G** level of theory. All calculations were carried out using Gaussian 03 program packages. The ground state geometries of molecule have been fully optimized both models without constrains. The calculated HF/6-31++G** and B3LYP/6-31++G** torsional angle for the syn-guache structure are, respectively, 61.9 degrees and 53.9 degrees with the corresponding values for anti-guache form being 122.8 degrees and 134.9 degrees. The conformational analysis was carried out by changing the torsional angle (phi), dihedral angle between phenyl and thiophene rings) by 10 degrees step between 0 (syn-planar) and 180 degrees (anti-planar). For each conformation, phi was held fixed while the remaining variables were fully optimized. The HOMO-LUMO energy difference and polarizability values of the molecule as a function of the torsion angle were calculated using B3LYP/6-31++G** level of theory.