The integration of Traditional Chinese Medicine (TCM) and Western medicine enhances our understanding of human physiology and offers innovative diagnostic and therapeutic approaches. Yin-Yang theory, a foundational concept in TCM, was first documented in the Yi Canon and later elaborated in Huang Di Nei Jing. As TCM continues to evolve alongside modern medical advancements, the Yin-Yang framework has gained broader scientific significance. This paper explores the relationship between Yin-Yang theory and physiological principles, its connection with contemporary medical theories, and its potential clinical applications. Specifically, it examines the structural and functional aspects of Yin-Yang, its material basis, and its role in integrative medicine.