Hypertension is a predictor for impaired cognitive function and dementia in several prospective studies. It is currently under debate whether treatment of hypertension, and thus blood pressure lowering, is another risk factor for cognitive decline. We recruited a sample of 123 treated hypertensive patients and 76 normotensive controls, from a population-based study in primary health care, for screening of blood pressure, metabolic variables and cognitive function, as measured by the Mini-Mental State Examination (MMSE). Treated hypertensives had higher blood pressure but did not differ in cognitive function from the normotensives. Neither educational level nor metabolic variables confounded the findings. In conclusion, treated hypertensives did not differ in cognitive function from normotensive controls. This does not support the notion that pharmacological blood pressure reduction impairs cognitive function.