Purpose: Conventional Doppler echocardiographic assessment of left ventricular (LV) function has some limitations. Recent studies suggested that global strain rate reflects myocardial function more accurately and strain rate measured during isovolumic relaxation (IVR) period is related well to hemodynamic indices of left ventricular relaxation both in animal model and in patients. The purpose of this study was to validate diastolic strain rate during isovolumic relaxation time (IVRT) in hypertensive patients with left ventricular hypertrophy (LVH) by two dimensional ultrasound speckle-tracking imaging (2DSTI). We also compared these data with patients who have hypertension without LVH and normal control group. Methods: 15 hypertensive patients with LVH (group 1), 40 hypertensive patients without LVH (group 2), and 15 healthy control subjects (group 3) were investigated. Strain rate curves were obtained using apical approach, and standard echocardiogram with tissue Doppler image was performed as a global diastolic index. LV longitudinal strain, peak strain rate IVRT (IVRT SR), peak early diastolic strain rate (E SR), peak late diastolic strain rate (A SR) were measured by 2DSTI. Results: E/E��� was significantly higher in group 1 and IVRT SR, E SR, A SR were significantly lower in group 1 compared with group 3 (p =0.01, 0.001, 0.042, 0.02 respectively), and IVRT SR was significantly different between group1 and group 2 as well. In multivariate logistic regression analysis, IVRT SR remained statistically significant predictors of left ventricular relaxation abnormalities in hypertensive patients with LVH (Hazards ratio: 61.615 (1.765-5.454), P = 0.020). IVRT SR also showed positive correlation with E/A and negative correlation with E/E��� in group 1 (r = 0.668, p = 0.005 ; r = -0.595, p = 0.019, respectively). Conclusions: Global IVRT SR by 2-dimensional speckle tracking was significantly lower in hypertensive patients with LVH than normotensive group. IVRT SR strongly indicates that it may be useful index for the assessment of left ventricular diastolic dysfunction.