The aim of this study was to compare the effect of valsartan/amlodipine and atenolol/amlodipine combination in preventing the recurrence of atrial fibrillation (AF) in hypertensive diabetic patients with a history of recent paroxysmal atrial fibrillation. Two hundred ninety-six hypertensive patients with well-controlled type 2 diabetes in sinus rhythm but with at least 2 ECG-documented episodes of AF in the previous 6 months were randomized to 160 mg of valsartan plus amlodipine (titrated from 2.5 to 10 mg) or to 100 mg of atenolol plus amlodipine (2.5 to 10 mg) in addition to their previous antiarrhythmic treatment (if any) and were followed up for 1 year. Blood pressure (BP) and a 24-hour ECG were evaluated monthly. The patients were asked to report any episode of symptomatic AF and to perform an ECG as early as possible. SBP/DBP values were significantly reduced after 12 months with valsartan/amlodipine (from 150.4/93.5 to 126.37/7.4 mm Hg, P < 0.001) and atenolol/amlodipine (from 151.1/94.2 to 127.1/77.9 mm Hg, P < 0.001), with no difference between the 2 regimens. At least 1 ECG-documented episode of AF was reported in 20.3% of the patients treated with valsartan/amlodipine and in 34.1% of those treated with atenolol/amlodipine, with a significant difference between treatments (P < 0.01). The positive effect of valsartan/amlodipine combination on AF recurrence was more evident in patients treated with amiodarone or propafenone than in patients treated with other antiarrhythmic drugs or without antiarrhythmic treatment. Despite similar BP reduction, valsartan/amlodipine combination was more effective in patients treated with amiodarone or propafenone than atenolol/amlodipine in preventing new episodes of AF in hypertensive diabetic patients.