Improvement in systolic functions after CRThas been well-established, but the effect on Left Ventricular (LV) diastolic functions is variable and not well established. The aim of this study is to analyze the improvement in diastolic functions of the heart after CRT. Total 67 cases of Heart Failure (HF) eligible for CRT (mean age, 62.5 ± 11.73 years; 54 males and 13 females) with Left Ventricular Ejection Fraction (LVEF) ≤35% or New York Heart Association (NYHA) Class II, III / Ambulatory IV (IVA) were included in the study. LVEF, pulsed-wave Doppler (PWD) derived transmitral filling indices (E and A wave velocities, E/A ratio), and peak early diastolic longitudinal myocardial velocity (E´) wave by tissue doppler were measured pre and post CRT and were compared. Left Ventricular Ejection Fraction (LVEF) increased >5% (responders) in 42 of 67 patients (62.6%) which was also associated with a reduction in pulsed-wave Doppler (PWD) derived indices that is E velocity, E/A ratio and E/E’ ratio while in non-responders (LVEF<5%) the E velocity, E/A ratio, E’ did not show significant change but E/E’ reduced significantly after CRT. Left Ventricular Diastolic functions improved significantly after CRT in responders but not in non responders.