Benzimidazoles 1-4 were obtained using modified synthesis methods and studied for their ability to inhibit cell proliferation of colon cancer cell HCT-116 and breast cancer cell MCF-7 using MTT assays. In the HCT-116 cell line, benzimidazole 2 was found to have an $IC_{50}$ value of $16.2{pm}3.85{mu}g/mL$ and benzimidazole 1 a value of $28.5{pm}2.91{mu}g/mL$, while that for benzimidazole 4 was $24.08{pm}0.31{mu}g/mL$. In the MCF-7 cell line, benzimidazole 4 had an $IC_{50}$ value of $8.86{pm}1.10{mu}g/mL$, benzimidazole 2 a value of $30.29{pm}6.39{mu}g/mL$, and benzimidazole 1 a value of $31.2{pm}4.49{mu}g/mL$. Benzimidazole 3 exerted no cytotoxity in either of the cell lines, with $IC_{50}$ values $>50{mu}g/mL$. The results suggest that benzimidazoles derivatives may have chemotherapeutic potential for treatment of both colon and breast cancers.