Erectile dysfunction is one of the major obstacles for noncompliance in the antihypertensive treatment. It has been shown that various antihypertensive drugs have a negative influence on sexual activity such as diuretics and beta-blockers. Thus, the purpose of the present study was to evaluate the effect of valsartan, an AT1-receptor antagonist, or its combination with hydrochlorothiazide on sexual activity in hypertensive patients. A total of 2202 patients (mean age 5478 years) with hypertension systolic blood pressure (SBP) greater than or equal to 140 mmHg, diastolic blood pressure (DBP) greater than or equal to 95 mmHg), or with pretreated hypertension, were included in the present analysis. Blood pressure was measured at baseline, after 8 and 16 weeks, respectively. Sexual activity was assessed with a questionnaire at each of the three visits. Sexual activity ( intercourse per week) was determined in three groups: controls (n = 27; conventional therapy); valsartan group n = 1899); valsartan in combination with hydrochlorothiazide (n = 276). There were 26 drop outs. SBP (-18.6 mmHg) and DBP (-11.6 mmHg) decreased significantly in all three groups. Sexual activity decreased slightly in controls from 1.3 to 0.9 times per week (NS), whereas it increased in the valsartan group from 1.0 to 1.6 times during follow-up (P < 0.0001). Similarly, sexual activity increased in the combination group from 0.9 to 1.3 times per week during follow-up (P < 0.0001). No sexual activity was reported by 467 (21%) of the 2202 patients at baseline and 154 (7%) at 16 weeks follow-up (P < 0.05). Impaired sexual activity is common in hypertensive patients (app. 20%). Valsartan increases the rate of sexual intercourses per week, whereas conventional therapy affects sexual activity adversely.