Angiotensin II (Ang II) type 1 (AT1) receptor is a member of the G protein-coupled receptor superfamily and contains 359 amino acids. AT1 receptor blockers (ARBs, e.g., eprosartan, losartan, candesartan, valsartan, telmisartan, olmesartan, irbesartan, and azilsartan) have been developed and are available for clinical use, and basic and clinical studies have shown that ARBs are useful for preventing the development of cardiovascular disease. While most ARBs have common molecular structures (biphenyl-tetrazol and imidazole groups), they also show slightly different structures. Some of the benefits conferred by ARBs may not be class-specific effects, and instead may be molecule-specific effects. Their common molecular structures are thought to be responsible for their class effects, whereas their slightly different structures may be important for promoting molecule-specific effects. This review focuses on current evidence regarding the class- and molecule-specific differential effects of ARBs from basic experiments to clinical settings.