Abstract: Robert K. S. Lim is recognized as the founding figure of modern physiology in China, embodying multiple identities as an overseas Chinese, medical scientist, and patriot, as well as a key architect of modern China's medical and nursing systems. As a distinguished physiologist, he dedicated his research to the fields of digestive physiology and pain physiology, established the Chinese Physiological Society, and served as the editor-in-chief of The Chinese Journal of Physiology. As a steadfast patriot, he developed and advanced the military medical and rescue systems during the Sino-Japanese War. This article aims to contextualize Lim's life and achievements within the frameworks of modern Chinese history and medical history, offering an in-depth exploration of his remarkable contributions to physiological research and the establishment of military medical systems in modern China.