Background: Coronary artery spasm is associated with vascular smooth muscle hyper-reactivity. Statin suppresses coronary spasm by inhibiting vascular smooth muscle contraction. However, the benefit of statin therapy in patients with coronary spasm-induced acute myocardial infarction (AMI) is unclear. Methods: A total of 37,617 consecutive patients were enrolled in the Korea AMI Registry from November 2005 to October 2013. Of these patients, we evaluated 501 patients (median age, 57 years; male/female, 346/155) who had coronary spasm-induced AMI with nonobstructive coronary arteries (stenosis severity,