Coronary arteriography (CAG) is one of the gold standards for diagnosing the severity of ischemic heart disease (IHD). Characterization of the angiographic findings of the focal coronary lesion was discussed on the basis of Rosch's and American Heart Association (AHA) classification. Recently, progression and regression of coronary atherosclerotic lesions have been assessed by serial CAG. Regression was believed to result from the dissolution or remodeling of thrombus or from the removal of plaque lipid and cellular elements. Accordingly, we also discussed the pitfalls in the evaluation of coronary stenosis. Recent modalities including intravascular ultrasound (IVUS) and angioscopy have been applied to assess the maternal characteristics of coronary atherosclerotic lesions, such as soft plaque, hard plaque, and calcification along with the extent of intimal thickening.