Spontaneous coronary dissection is a rare cause of myocardial ischemia, myocardial infarction and sudden cardiac death. Idiopathic spontaneous coronary artery dissection (SCAD) occurs in patient without risk factors for coronary artery disease and without underlying pregnancy. We describe a case of idiopathic spontaneous coronary dissection after sleep deprivation presenting with acute myocardial infarction. A 40 year old woman presented to an emergency department with squeezing substernal chest pain lasting 1 hour following 72 h sleep deprivation due to overtime work. On admission, ECG showed no significant ST change. But the level of CK-MB and Troponin T were increased up to 77.54 ng/ml and 1.62 ng/ml, respectively. Emergent coronary angiography demonstrated a longitudinal dissection of the middle portion in the diagonal artery with TIMI III flow to the distal part of the vessel. Because the dissected vessel was too small to pass the intravascular ultrasound (IVUS) and deploy the stent, angioplasty was not performed. Under medical treatment with aspirin, clopidogrel and unfractionated heparin, conservative management was proposed; she remained free of symptom and discharged free of chest pain and in good condition.