Objectives : This study was undertaken in order to establish the composite principles of fomulas through the of Sa-am acupuncture therapy and the theory of sovereign, minister, assistant and courier. Methods : We analyzed the formula construction of Sa-am acupuncture therapy, and applied the theory of sovereign, minister, assistant and courier that was referred to in the preface of "Essential Rhymes on Acupuncture and Moxibustion by Master Sa-am" to the analysis of formula construction. Results & Conclusions : 1. Sa-am acupuncture therapy was acupuncture and moxibustion method that inherited and developed progress contents of Chinese traditional acupuncture and moxibustion. 2. The theory of sovereign, minister, assistant and courier was based on the idea that acupuncture and herbal medicine had the same origins. 3. Formula constructions of Sa-am acupuncture therapy were formed complicatedly, but reflected the theory of sovereign, minister, assistant and courier. 4. The supplementing acupuncture point that is Chunbu-point in other merdian became Sovereign, the draining acupuncture point that is Chunbu-point in other merdian became Minister, and the supplementing and draining acupuncture points in same merdian became Assistant and Courier that mean leading merdian points.