A series of benzimidazole derivatives bearing a heterocyclic ring imidazole (1), 5-chloroimidazole (2),1,2,4-triazol (3), and imidazoline (4) were synthesized and evaluated for angiotensin II antagonistic activities.The synthetic compounds 1–4 were biologically evaluated in vitro using an AT1 receptor binding assay, where compounds 1 and 3 provided weak binding affinity, compound 2 showed moderate binding affinity, and compound 4 showed good binding affinity. Moreover, compound 4 was found to be almost equipotent with telmisartan in vivo biological evaluation study.