Concept of Cho was used both etiologically and symptomatically at the same time. Hwa was the main cause of diseases derived from Cho, and its damage is on Jin-Eum. Cho is one of the members of Euk-Eum, which belongs to Whae-In, but it is also recognized as pathogen of internal dysfunction, therefore symptoms can be classified into two groups. Whae-cho-zheung and Nae-cho-zheung. Organs related to Cho are lung, stomach, intestine, kidney, liver and gall Bladder. Symptoms of Whae-cho usually combines Pyo-zheung, manifesting on lung and skin, whereas symptoms of Nae-cho combines Rhee-zheung, manifesting on internal organs and tissues. In treating of Cho, Ja-eum-yang-hyul-chung-yeolis the main principle. Chung-Yun-Pe-Weis used in Whae-cho-zheung and Sang-cho-byung, while Yu-Yang-Gan-Shin is used in Nae-cho-zheung and Ha-cho-byung.