Coronary artery disease is the major cause of death in developed countries. PET myocardial perfusion image has become more important in the diagnosis and risk stratification for coronary artery disease patients. The available evidence supported that PET is the “gold standard” for detecting myocardial perfusion, comparing to other noninvasive assessment techniques. Its ability to quantify absolute myocardial blood flow and evaluate left ventricle function from rest to stress provides an extra value in multi-vessel disease and prognosis. As the development of scanners, software, novel radiotracers, hybrid imaging technique and the emerging clinical evidence, the clinical application of PET will be further enhanced in the near future. This review summarized clinical application of PET myocardial perfusion imaging and its new developments.