Twenty-four 1,2-diarylbenzimidazole derivatives were designed, synthesized and biologically evaluated. It turned out that most of them were potential anticancer drugs. Among them, compound c24 showed the highest anti-tumor activity (GI = 0.71-2.41 μM against HeLa, HepG2, A549 and MCF-7 cells), and low toxicity to normal cells (CC > 100 μM against L02 cells). In the microtubule binding assay, c24 showed the most potent inhibition of microtubule polymerization (IC = 8.47 μM). The binding ability of compound c24 to tubulin crystal was verified by molecular docking simulation experiment. Further studies on HepG2 and HeLa cells showed that compound c24 could cause mitotic arrest of tumor cells to G2/M phase then inducing apoptosis. To sum up, compound c24 is a promising microtubule assembly inhibitor.