Abstract：The “Spleen-Yin Theory”is the integral part of doctrine of visceral manifestation in Chinese medicine with deep theoretical connotation. As the origin of “Spleen-Yin Theory”，Huang Di Nei Jing (The Yellow Emperor's Inner Classic) lays its theoretical foundation；in the Shang Han Za Bing Lun (Treatise on Cold Damage and Miscellaneous Diseases)， Maimendong Decoction， Shuyu Pills and Maziren Pills were created，which provided the basic idea of syndrome differentiation and prescription selection. The ancient physicians in Tang，Song and Yuan Dynasties supplemented the theory，and it was perfected in Ming and Qing Dynasties. In modern times， many scholars have carried out relevant clinical studies by applying the “Spleen-Yin Theory” to guide the treatment of such diseases as diabetes and atrophic gastritis， which suggests new thoughts on diagnosis and treatment. The “Spleen-Yin Theory” has important clinical relevance.