Cardiovascular measurment on PA teleroentgenogram of the chest is simple, but very useful I the diagnosis, prognosis, and therapy of hypertensive patients. The authors have measured and calculated cardiothoracic ratio, Lt. to Rt. cardiac diameter raio, and Lt. aortic knob width to thoracic diameter ratio for evaluation of the effect of blood pressure and age in hypertensive group. We used materials of 70mm fluorography of 255 hypertensive men above 150/90mmHg chosen from national police hospital during Jan. from Aug. 1981. Their age ranged from 20 to 50 years. The Results were as follows. 1. Cardiomegaly (above 50 percents in cardiothoracic ratio) of hypertensive men is 26%. 2. The cardiothoracic ratio increased progressively with blood pressure and age, but pooly correlated between crdiothoracic ratio and age than blood pressure. 3. The Lt. to Rt. cardiac diameter ratio gave similar trend to the cardiothoracic ratio. It indicates that hypertensive cardiac enlargement mainly depend on Lt. Ventricular enlargement. 4. The Lt. aortic knob width to thoracic diameter ratio increased progressively with blood pressure and age, and had linear correlatioship with blood pressure and age. Therefore, prominence of aortic knob is the most significant finding in hypertensive cardiovascular disease.