Early in the matriarchal society 4000 years ago, medical activities of the Yi-nationality had already begun. Through long process of struggle against diseases, the ancestor of Yi-nationality accumulated a huge wealth of medical knowledge, including acupuncture, medicinal wine and herbs, from which the theory of "Ba Fang" (eight-direction) "Ba Jiao" (eight-corner) and Yin-Yang system were formed, and became the core of rationale of Yi-medicine. Due to geographical reasons, Yi-medicine was isolated and scarcely communicated with the outside world. Hence, so far it preserves much of its own features and thus, it offers excellent materials for the studies on the provenance and development of the medicine of Chinese minorities.