Percutaneous transluminal coronary angioplasty (PTCA) is a nonoperative mechanical dilatation of atherosclerotic coronary artery stenosis by a balloon-tipped dilating catheter system. This method can effectively reduce highly stenotic coronary lesions and provide early recovery of ischemic but viable myocardium. The technique of transluminal angioplasty was originally devised by Dotter and Judkins (1964) for the treatment of atherosclerotic stenoses of peripheral arteries and was introduced in modified form by Grüntzig for the treatment of coronary artery disease in 1977. Recently this procedure seems to have been accepted world wide as one of the potential therapeutic modalities comparable to aorto-coronary bypass surgery in selected patients with angina pectoris. In this paper, the author introduced the present status of PTCA including his own data.