In this study the anticancer properties of a series of benzimidazole drugs 1 –9 and their inter-actions with DNA base pairs were investigated. The obtained theoretical results for anticancer activity of synthesized drugs 1 –5 were compared to corresponding published experimental results. Based on theoretical and published experimental anticancer scales, drugs 2 and 4 have higher anticancer activity among drugs 1–5. Obtained results reveal that interactions of studied drugs with DNA base pairs are energetically favorable and solvent and electric field (EF) increase the binding energies in comparison to gas phase. The binding energies of drugs 2, 5 and 4 with DNA base pairs are more negative than corresponding values for drug 1. We propose the novel drugs 6 –9 to synthesize with higher anticancer activity. Results show that binding en-ergies of novel drugs 6–9 were more negative than drugs 1–5. Finally, results show that chemical potential, electrophilicity and global hardness can be considered as admissible theoretical an-ticancer indexes for studied benzimidazole drugs 1 – 9.