Objective: To compare the effects of hydrochlorothiazide and indapamide combined with losartan on renal function and arterial stiffness in elderly hypertensive patients.Methods: One hundred twenty two elderly patients with hypertension (50％ male, mean age 69.52±10.55 years old)were randomized to treatment with 12.5 mg/d of hydrochlorothiazide (group 1, n =62) or 1.5 mg/d of indapamide (sustained release) (group 2, n =60) combined with losartan 50 mg/d after treatment only with losartan 50 mg/d for two weeks and failed to reach a target blood pressure (140/90 mm Hg).