The methodology of constitution diagnosis is main concern in sasang constitutional medicine, but highly reliable method is not yet established. So we statistically analyzed the relationship between the constitution and characteristic factors of skin such as thickness, stiffness, roughness, and touch-feeling, using 1079 clinical data registered to SCIB(Sasang constitution Information Bank), and the following results are obtained: The skin of Taeeumin are more thick or more stiff or more rough than other constitutions. The skin of Soeumin are more soft or more feeble or more feeble-refined than other constitutions. The skin of Soyangin are more slippery or more thin or more slippery-refined than other constitutions. The differences written above were proved to be meaningful enough by Chi-square test.