Objective The aim of this study was to approach the effects of percutaneous transluminal coronary angioplasty (PTCA) and stenting on QT dispersion (QTd) in patients with coronary heart disease. Methods PTCA and stenting were performed successfully on 42 patients with coronary heart disease. QTd and corrected QTd (QTcd) were obtained with a standard 12-lead ECG before and after PTCA+ Stent. Results QTd and QTcd after PTCA+Stent were reduced significantly compared to those before PTCA+Stent (P<0.01). There were no significant difference in QTd and QTcd before PTCA+Stent between single vessel lesion and multi-vessel lesion, but after PTCA+Stent, QTd and QTcd in single vessel lesion were decreased significantly compared to those in multi-vessel lesion. The ventricular arrhythmia in 9 patients was over after PTCA+Stent. Conclusions QTd and QTcd were decreased significantly after PTCA+Stent because of the improvement of myocardial ischemia and heterogeneous repolarization in patients with coronary heart disease. The degree in decreasing QTd and QTcd was associated with compensatory circulation in coronary artery.