To compare quality of life with the selective beta1-blocker bisoprolol and the thiazide diuretic bendrofluazide in patients with mild to moderate hypertension. Multi centric, randomised, double-blind, two-way crossover study carried out at six general practice centres. Eighty-one patients with newly diagnosed or previously treated hypertension, who had a mean diastolic blood pressure (BP) of 95-120 mm Hg after receiving placebo for 4-6 weeks. In random order, patients received bisoprolol (5 mg once daily) or bendrofluazide (2. 5 mg once daily) for 8 weeks. Quality of life and antihypertensive effect. Decrease in systolic/diastolic BP did not differ between bisoprolol (10 +/- 2/13 +/- 1 mm Hg) and bendrofluazide (9 +/- 2/11 +/- 1 mm Hg). Between bisoprolol and bendrofluazide neither in the intention-to-treat nor in the efficacy analysis any difference was found in quality of life variables, such as Health Status Index, somatic symptoms, anxiety, depression, total psychiatric morbidity, cognitive symptoms and hostility score. Compared to baseline the Health Status Index improved (P < 0.05) during bisoprolol. None of the other investigated quality of life variables changed compared to baseline. No patients dropped out during bisoprolol or bendrofluazide treatment. Although, the total number of reported adverse events appeared lower during bendrofluazide than during bisoprolol treatment, it is unclear whether drug related adverse events also differ between the two drugs. At equipotent antihypertensive dosages, the effect of an 8-week treatment on quality of life does not differ between the selective beta1-blocker bisoprolol and the thiazide diuretic bendrofluazide.