Objectives : In oriental medicine, many researchers have studied Myofascial Pain Syndrome and Twelve-Meridian Muscle system in correlation with the orthodox form of muscular anatomy. In this study, the authors compared Myofascial Pain Syndrome with Twelve-Meridian Muscle system and interpreted Myofascial Pain Syndrome through Yook Kyoung theory to reveal the similarity between Myofascial Pain Syndrome and Twelve-Meridian Muscle system, as well as to suggest another useful therapeutics. Methods : The authors investigated several literatures related with Myofascial Pain Syndrome, Twelve-Meridian Muscle system and Yook Kyoung theory. Conclusions : 1. Myofascial Pain Syndrome and Twelve-Meridian Muscle system have many similar features in their theory, concept, physiological function, pathological symptom, therapeutic principal, etc., also have some different features. 2. Myofascial Pain Syndrome is thought to be induced by the unbalance between the upregulated-Kwelum energy and the downregulated-Soyang energy in a viewpoint of Yook Kyoung theory, therefore, it is requisite to control the unbalanced energy between Kwelum and Soyang.