Background Arterial hypertension is one of the major cofounders in the development of atrial fibrillation (AF) and hypertension is commonly found in AF patients. The aim of the study was to establish the prevalence of arterial hypertension in patients undergoing ablation, who are relatively young and healthy group of AF patients. Material and methods 266 consecutive patients admitted for AF ablation were screened for arterial hypertension. All patients had their blood pressure measured on admission by, prior to the ablation procedure by a qualified physician, according to the current guidelines. Also, medical records of patients were reviewed for the previous diagnosis of hypertension or taking hypotensive agents. Results The study group was predominantly male (65.0%; mean age 57.6 ± 10.1 years). Mean body mass index was 29.7 ± 5.0 kg/m 2 . Paroxysmal AF was present in 69.5% of patients. In 72.9% of patients hypertension was diagnosed previously. On admission, mean systolic and diastolic blood pressure values were 131.7 ± 16.7 and 80.7 ± 11.1 mm Hg. 123 (46.2%) patients had systolic and/or diastolic blood pressure values respectively > 140 and/ /or > 90 mm Hg. Patients with previously diagnosed hypertension were older (58.7 ± 8.7 vs 54.6 ± 12.7 years; p = 0.003), had higher BMI (30.3 ± 5.0 vs 28.1 ± 4.8 kg/m 2 ; p = 0.002), and more often history of diabetes (10.8% vs 1.4%; p = 0.03) compared to non-hypertensive group. There were no differences in terms of history of dyslipidaemia, stroke, myocardial infarction or family history of cardiovascular disease. Conclusions In patients with AF undergoing ablation procedure, prevalence of diagnosed arterial hypertension is very high, much higher than in the general population. Nevertheless, majority of patients meet the criteria for adequate blood pressure control. key words: arterial hypertension, atrial fibrillation, ablation