=The main purpose of this study is to differentiate Sasang Constitutions of men and women by measuring 5 parts of the body. By the definitions about Four Chos(四焦) in ${\ulcorner}$The Discourse on Viscera and Bowels(臟腑論)${\lrcorner}$, the body is divided into four parts and sets up the five borderlines. They are Top-line, Bosom-line, Stomach-line, Navel-line and Bottom-line. Top-line(第一線) is the horizontal distance between Rt. & Lt. Coracoid processes passing through the acupuncture point CV-22(天突穴) or the horizontal distance between Rt. & Lt. beginning points of Axillary lines. Bosom-line(第二線) is the horizontal distance passing through Rt.& Lt. Nipples. Stomach-line(第三線) is the horizontal distance passing through Rt.& Lt. acupuncture point ST-19(不容穴). Navel-line(第四線) is the horizontal distance passing through the navel(CV-8; 神闕穴) and the acupuncture point ST-25(天樞穴). Bottom-line(第五線) is the horizontal distance between Rt. & Lt. Anterior Superior Iliac Spine(ASIS). The measured numerical values of Five Lines are the most important factors to classify the Four Constitutions(Taeyangin, Taeumin, Soyangin, Soeumin). Among the five lines, Stomach-line(Middle-line) is the base line to decide Yin and Yang. As a result, I could differentiate the four Constitutions as follows. 1. Taeyangin's Top-line is more than 36cm long. Top-line is the longest. Bottom-line is the shortest. The length-difference between Top-line and Bottom-line is more or less 10cm long. 2. In case of Taeumin, Navel-line is the longest. The numerical values of Middle and Bottom lines are almost the same or Bottom-line is shorter than Middle-line by 1 or 2 cm long. In some special case, the five lines are all the same and the body just looks like a log. 3. In case of Soyangin, just like Taeyangin, Top-line is the longest. Bottom-line is the shortest. The length of Top-line is ranged between 30cm to 35cm long. From Top-line to Bottom-line, the length gradually diminishes each by 2cm: for example, 34-32-30-28-26. 4. In case of Soeumin, the longest one is Bottom-line. Specially, Navel-line is shorter than Middle-line. Bottom-line is longer than the Middle.