In this paper, the philosophy and the content of medicinal philosophy of Lee Jae-Ma were illuminated through the history and philosophy of the late Choseon times from 1837 to 1900. Some conclusions were as follows: 1. Lee Jae-Ma was a philosopher as well as a doctor, and his philosophical background was well appeared in the book of . 2. Although the philosophy of Lee Jae-Ma and its terms were derived from the Kyunghakseol of Confucianism, the concept of these terms was different from the Neo-confucianism of Song Dynasty in China. 3. The four phases of the philosophy of Lee Jae-Ma was originated from the four important trigrams, however, he did not take the meanings of the changes and development of the trigrams in , but also took the four components of construction of cosmos similar to the Western theory of four component. 4. It is unreasonable that he is categorized in the group of the scholars of anti-Chu-tzu and neo-confucianist since the theory of the four phases was originated from the Kyunghakseol of Confucianism and also neo-Confucianism. 5. Dong Mu took the dualistic theory of mind and body in Ho Chun's as the core of his thought, but Dong Mu's method of the explanation was not based on the Taoism, the key of the thought of , but based on the Kyunghakseol of Confucianism. 6. Dong Mu wrote the two medicinal books and based on the thought of regimen of . But the philosophy of his books was based on the thought of Confucianism, not on of the nature of Taoism.