ABSTRACT Objective The purpose of this study was to investigate the relationship between fragmented QRS(fQRS) and intraventricular dyssynchrony in patients with CAD. Methods 176patients with CAD were recruited. The fQRS included various RSR’patterns without typical bundle branch block on a 12-lead ECG in 2 contiguous leads corresponding to a major coronary artery territory. Intraventricular dyssynchrony was evaluated with Tissue Doppler imaging echocardiography. Results There was 55 (31%) patients in present fQRS (fQRS group) and 121(69%) patients in absent fQRS(non-fQRS group). Indices of intraventricular dyssynchrony including Ts-12 (128.8ms±49.6ms vs. 110.6ms±46.3ms, P=0.019) and Ts-SD (43.7ms±17.7ms vs. 37.8ms±17.4ms, P=0.04) were significantly prolonged in fQRS group compared to non-fQRS group. In addition, the proportion of LV dyssynchrony was significantly higher in patients with fQRS compared to those without fQRS (75%vs. 58%, P=0.033). Multivariate analysis revealed that Ts-SD (Odd ratio[OR]1.06, 95%confidence interval[CI]1.01-1.11, P=0.016) and multivessel lesion (OR 2.85, 95%CI：1.27-6.41，P=0.011 ) were independent predictors for fQRS. Conclusion Fragmentation of QRS complexes on ECG are associated with intraventricular systolic dyssynchrony in patients with CAD, suggesting that depolarization abnormality may contribute to intraventricular dyssynchrony. [Keywords] Fragmented QRS；Coronary artery disease；Synchrony；Tissue Doppler