【Abstract】 Atrial fibrillation (AF) is a multifaceted condition with several potential contributing factors.Thyroid hormone may exert both genomic and nongenomic roles in the cardiovascular homeostasis.AF occurs in up to 15% of patients with hyperthyroidism,and is more common in men than in women.Experimental and clinical investigations showed that overt and subclinical hyperthyroidism are risk factors associated with the development of AF.As the most common cardiac complication of hyperthyroidism,AF is a complex disease with several possible mechanisms.The main goal of this review is to discuss the clinical and pathophysiological links between hyperthyroidism and AF,and its underlying molecular mechanisms.