To evaluate the cardiac functions we examed the M-mode echocardiography with measurements of blood pressure, heart rate and body surface area in 55 normal Korean adults(male 30 persons, female 25 persons) of mean age, 41.7+/-12.3 years. (1) Interventricular septal thickness is 9.5+/-1.7mm and left ventricular posterior wall thickness are 8.6+/-1.5mm at end-diatole, 14.0+/-2.1mm at end-systole. (2) Diastolic and systolic left ventricular internal dimensions are 49.1+/-4.8mm and 31.3+/-5.0mm, respectively. (3) Left ventricular mass by Penn Convention method is 174.4+/-52.1g and left ventricular mass index is 103.2+/-28.8g/m2. (4) Relative wall thickness is 0.35+/-0.06. (5) Left ventricular volumes by Teichholz's method are 114.9+/-27.6ml at diastole and 40.2+/-17.2ml at systole. Therefore, stroke volume is 74.7+/-16.9ml and stroke volume index is 44.5+/-10.7 ml/m2. (6) Cardiac output is 4944+/-1058 ml/min and cardiac index is 2951+/-666 ml/min/m2. (7) Total peripheral resistance is 1454+/-356 dynes-sec-cm(-5) and total peripheral resistance index is 2472+/-623 dynes-sec-cm(-5).m2. (8) Fractional shortening is 36.5+/-6.0% and pressure-volume ratio is 3.27+/-1.19 mmHg/ml. (9) End-systolic wall stress is 61.3+/-19.7x10(3) dynes=cm2. (10) Atrial emptying index is 0.66+/-0.18.