The middle reaches of the Han River, as a transitional zone for the integration of southern and northern opera cultures, are the core field for the southern transmission and localization evolution of the Central Plains Yuediao. The existing research on Yuediao mainly focuses on the origin of opera genres and singing techniques, lacking systematic research on the correlation between watershed geography, immigration history, and vocal changes. This article takes Xiangyang, Laohekou, Gucheng and other areas in the middle reaches of the Han River as the research scope. Based on first-hand field research data, it explores the core driving forces of the flow of Yuediao theatrical troupes and the evolution mechanism of localized singing from three dimensions: watershed space, immigrant migration, and local customs. Research has shown that the Han River system has built a spatial corridor for the dissemination of traditional Chinese opera, Ming and Qing immigrants have provided a carrier for cultural heritage, and local customs have shaped the survival ecology of traditional Chinese opera. Together, these three factors have promoted the comprehensive regional reconstruction of the Central Plains Yuediao from the flow of troupes, accompaniment system, and aesthetic core to dialect phonetics, forming a unique Xianghe Yuediao vocal system.