I studied on the correlativity with an individual constitution and etiological factor, the results are as follows. As the external wickedness invade into human body, the condition of an individual constitution determine whether being attacked with a disease or not. Moreover the contracting and the tendency of a disease are determined from the peculiarity of an individual constitution. And whether being attacked with a disease or not, the contracting and the tendency are possible explained of DONG-GI-SANG-GU(the indentical vigour looking for mutually). The division on the malice for cause of a disease and the symptom of a disease are more and more necessary.