Background/Aim. Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in general population. The aim of the study was to compare all-cause mortality and cardiovascular mortality in patients with lone and idiopathic AF to correspondent mortality in general population of Serbia. Methods. A longitudinal observational study included the patients with nonvalvular AF as the main indication for inhospital and/or outpatient treatment in the Clinical Center of Serbia, during a period 1992-2007, if the latest date of first diagnosed AF was early January 2003; in that way, the total follow- up could last at least 5 years (minimum 1 year prospectively), or until death. Principles of oral anticoagulation, heart rhythm and frequency control during the study period were conducted according to the latest international guidelines for diagnosis and treatment of AF in the study period. Lone and idiopathic AF were defined as AF in patients without any underlying disease, younger than 60 years (lone AF) or older (idiopathic AF). To compare mortality of the study population with mortality of general population we used the standardized mortality ratio (SMR) and chi-square test with p < 0.05 as a level of statistical significance. Results. Out of 442 patients with AF and no underlying disease, aged 47 ± 12.6 years, with mean follow-up of 11.5 ± 7.2 years, 12 patients (2.7%) died: 7 patients of non-cardiovascular causes and 5 patients (1.1%) of cardiovascular death. When compared to the general population of Serbia, all-cause mortality and cardiovascular mortality in the patients with lone and idiopathic AF were not higher than in general population (p < 0.05). Conclusion. All-cause mortality and cardiovascular mortality of patients with lone and idiopathic AF are similar to all-cause mortality and cardiovascular mortality in general population of Serbia.