To confirm age-related changes in left and right ventricular filling velocity profiles and to compare left and right ventricular filling parameters in normal subjects, we performed pulsed Doppler echocardiographic studies in 108 normal subjects (72 men and 36 women) aged 15 to 78 years. An age-related decrease in peak early velocity (E velocity), an increase in peak atrial velocity (A velocity), and augmented ratio of A velocity to E velocity (A/E) were observed in left ventricle (r = -0.71, 0.63, and 0.83, respectively). Similar age-related changes were found in right ventricle (r = -0.71, 0.54, and 0.78). Aging had a greater effect on the filling of the left ventricle than the right one (i.e., a steeper slope). The difference between left and right ventricular filling increased with advancing age. Left ventricular filling indexes exceeded those of the right ventricle. Significant correlations were observed between the right and left ventricular filling parameters (r = 0.58 to 0.90). A strong relation was noted in A/E (r = 0.90). There was no significant relation between age and left ventricular mass. The left ventricular mass appeared to have little effect on left and right ventricular filling in normal individuals. Thus in clinical studies the age-related decrease in early diastolic filling and the increased atrial filling in both left and right ventricles should be considered. The atrial contribution to ventricular filling may be more pronounced in the left ventricle than the right ventricle in older subjects.