Abstract: The Chinese sturgeon (Acipenser sinensis) is a nationally protected wild animal of first-level importance, and the Pearl River basin was once the type locality for this species. This paper systematically reviews the reproductive ecological characteristics and regional extinction process of the Pearl River population of Chinese sturgeons. The breeding season of the Pearl River population extends from early March to early April, with parent fish migrating upstream along the Xijiang River, Xunjiang River, Qianjiang River, and Liujiang River. The core spawning grounds are located in the sections of the Liujiang River at Henggucai and the Qianjiang River at Yubu. Since 2003, there have been no reliable wild observation records for this population, and it was confirmed to have undergone regional extinction in the early 21st century. The phenological characteristics of its spring breeding differ from the autumn and winter breeding phenology (mid-October to early November) of the Yangtze River population, forming temporal reproductive isolation. Comprehensive analysis indicates that the decline of the Pearl River population is a result of multiple stressors, including the obstruction of migration routes due to hydropower development, overfishing, and the degradation of spawning ground hydrology and sediment quality. From 1996 to 2002, it exhibited a “sudden collapse” characteristic. Current measures include fishing bans, habitat restoration and ecological regulation, fishway construction, and ex-situ conservation, but they face key bottlenecks: the released parent fish have long relied on “Yangtze River lineage” germplasm resources and are genetically unadapted to the spring breeding environment of the Pearl River, making it difficult for artificial reconstruction to form a self-sustaining wild population. This paper suggests: given the regional extinction of the native population in the Pearl River, relying on existing historical specimens to trace residual genetic imprints and systematically screen for potentially remaining spring breeding-related genotypes in the Yangtze River population. At the same time, a long-term monitoring system encompassing environmental DNA analysis, acoustic telemetry, and traditional fishing techniques should be established. It is called for to incorporate the independent conservation value of geographical populations into the species endangerment assessment framework.