Diffusion MR is challenging in myocardium because of respiratory motion, cardiac pulsation, and field inhomogeneity in thorax. Diffusion tensor imaging using SE-EPI with respiratory navigation and cardiac triggering of 3 b values (300, 500, 800 s/mm2) was performed in 9 subjects. Sufficient image quality was obtained with b values of 300 and 500 s/mm2. Significant difference was found in SNR, CNR, MD, and FA between various b values while not between myocardium segments. Intermediate b values are recommended to achieve a balance of image quality and diffusion sensitivity . Sufficient myocardium quiescent duration is extremely important for optimal diffusion image quality.