To evaluate the changes of Doppler echocardiographic parameters of left ventricular(LV) filling in hypertensive subjects, 34 patients(M : F=17 : 17) with and without LV hypertrophy and 19 healthy, age-matched control subjects(M : F=10 : 9) were examined by M-mode, 2 dimensional and Doppler echocardiography. From the Doppler recording, A₂ D(time from second heart sound to the onset of early diastolic mitral flow), peak velocity at early diastole(E) and late diastole(A), ratio of E to A velocity, diastolic filling times, early diastolic deceleration rate(EDDR) and flow velocity integral(FVI) were measured. In the patients without LV hypertrophy, A₂ D only was significantly prolonged(127±21 vs 83±24 msec P<0.01) as compared with the normal subjects, but the patients with LV hypertrophy had more prolonged A₂ D(149±31 vs 83±24 msec P<0.01), higher late diastolic peak velocity(A : 0.58±0.17 vs 0.47±0.09m/sec, P<0.01) and lower E/A velocity ratio(0.95±0.19 vs 1.24±0.29, P<0.01) than the normal subjects. There was a significant correlation between A₂ D and LV muscle mass index in entire patients with hypertension(r=0.42P<0.01). These data suggest that A₂D is the earliest parameter indicating abnormality of LV diastolic function and E/A ratio is not likely to be a definite index of LV diastolic dysfunction but rather be a reliable index of LV hypertrophy in hypertensive patients with preserved LV systolic funtion.