This article examines the relationship between science and ideology through the case study of Bong Han(鳳漢)theory in North Korea. In the 1960s a medical doctor Bong Han Kim reported a theory demonstrating the independent existence of Kyungrak(經絡) system which had been known as the flowing route of Ki(氣) in oriental medicine. Some party technocrats picked up and highlighted the theory as a major scientific accomplishment embodying the independent political line which they began to pursue with a feverish enthusiasm. With support from the political regime, the theory became well-refined with elaborate and advanced experimental techniques in its methodology but at the same time it is increasingly stained with the political ideology in its content. As the Bong Han theory was hailed as "a communist science", it exerted a deep influence on North Korean society: for example, the Bong Han theory helped oriental medicine to be established as an academic discipline and also helped the independent political line to develope into Juche(主體) thought that had been diverging from the orthodox socialism. The Bong Han theory soon turned out to be unreasonable as a scientific theory, nevertheless, its ideological implications continued and spreaded powerfully with vitality.