Benzimidazoles 1-4 were obtained using modified synthesis methods and studied for their ability to inhibitcell proliferation of colon cancer cell HCT-116 and breast cancer cell MCF-7 using MTT assays. In the HCT-116cell line, benzimidazole 2 was found to have an IC50 value of 16.2±3.85 μg/mL and benzimidazole 1 a value of28.5±2.91 μg/mL, while that for benzimidazole 4 was 24.08±0.31 μg/mL. In the MCF-7 cell line, benzimidazole4 had an IC50 value of 8.86±1.10 μg/mL, benzimidazole 2 a value of 30.29±6.39 μg/mL, and benzimidazole 1 avalue of 31.2±4.49 μg/mL. Benzimidazole 3 exerted no cytotoxity in either of the cell lines, with IC50 values >50μg/mL. The results suggest that benzimidazoles derivatives may have chemotherapeutic potential for treatmentof both colon and breast cancers.