This article examines the relationship between science and ideology through the case study of Bonghan 鳳漢theory in North Korea. In the 1960s a medical doctor Kim Bonghan reported a theory demonstrating the independent existence of gyeongrak 經絡 system which had known as the flowing route of qi 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 pur-sue with feverish enthusiasm. With support from the political regime, the theory be-came well-refined with elaborate and advanced experimental techniques in its meth-odology. But at the same time it was increasingly stained with political ideology in its content. As the Bonghan theory was hailed as “communist science,” it exerted a deep influence on North Korean society: for example, the Bonghan theory helped oriental medicine to be established as an academic discipline and also helped the independent political line to develop into Juche 主體 thought that had been diverg-ing from orthodox socialism. The Bonghan theory soon turned out to be unreasona-ble as a scientific theory. Nevertheless, its ideological implications continued and spread powerfully with vitality.