Purpose: The cardiac resynchronization therapy (CRT) can improve the heart function in patients with heart failure with left bundle branch block. Recently, it has been pointed out that even patients with normal QRS may exhibit intraventricular dyssynchrony (IVD). The aim of this study was to evaluate the incidence of IVD in patients with dilated cardiomyopathy with narrow QRS by tissue Doppler and strain image. Methods: We enrolled 22 non-ischemic dilated cardiomyopathy with narrow QRS (M:F 17:5, 52.7짹13.2). We measured the time from QRS onset to systolic peak in DTI and compression/expansion crossover point in the strain image at mid and basal segment of apical 4 and 2 chamber views. All data were corrected by heart rate. The IVD by DTI and strain image was defined as > 100 msec and > 215 msec, respectively in difference between maximum and minimum at all segments. Also, after corrected by heart, IVD by DTI and strain image was defined as > 4.0 and > 6.5 msec, repectively. Results: The IVD by DTI in patients with narrow QRS was 41.9% (9/22), and 18.2 % (4/22) after correct by heart rate. However, IVD by strain image was 77.3%(17/22), and 81.8%(18/22) after corrected by heart rate. Conclusion: In our study, the incidence of IVD in patients with dilated cardiomyopathy with narrow QRS was similar by using DTI with other report, however by using strain image, the incidence was higher than expected.