The prevalence of postural hypotension among over 65 year old men is 10-30%. The postural hypotension commonly causes the discomfort such as dizziness, irritability or fainting spell, and for the result it diminishes the quality of the life of aged. Therefore the assessment and intervention of postural hypotension during changing position is very important. The purpose of this study is to investigate the effect of changing position from supine to standing upright, from supine through left lateral to standing upright, from supine through sitting to standing upright of aged. The results obtained are as follows : 1. The average systolic blood pressure of normotension group is $132.68{pm}16.04mmHg$ at supine position. The average diastolic blood pressure of normotension group is $80.72{pm}9.82mmHg$ at supine position. The average systolic blood pressure of hypertension group is $153.92{pm}20.12mmHg$ at supine position. The average diastolic blood pressure of hypertension group is $93.74{pm}15.53mmHg$ at supine position. 2. There is no significant difference of blood pressure after three different procedures as mentioned above from supine to standing upright. 3. The prevalence of postural hypotension at standing upright is 13.5% which is 18.8% of the hypertension group and 9.4% of the normotension group. There is statistical difference of the prevalence of postural hypotension between hypertension group and normotension group.