Purple soils, rich in mineral nutrients due to their parent material characteristics, constitute an important type of cultivated soil in China"s subtropical regions. However, under the influence of modern soil-forming environments and human activities, significant yellowing and acidification have occurred in some areas of purple soil, marking its evolutionary process toward the development of zonal yellow soil. This process profoundly reshapes the physicochemical properties and ecological environment of the soil. However, current research on the mechanisms, soil characteristics, and ecological effects of purple soil yellowing remains unclear. This paper reviews research on purple soil yellowing, characterizing the phenomenon through multiple dimensions including morphology, physicochemical properties, mineralogy, and developmental features. It analyzes the mechanisms by which soil-forming factors, such as parent material, climate, topography, hydrology, vegetation, and human activities, influence the yellowing process. The study further examines the effects of yellowing on soil fertility and ecological environments. Finally, this study highlights current limitations in quantitative characterization, dynamic evolution mechanisms, spatial prediction, and precision management. It also outlines future research directions to deepen the theoretical understanding of purple soil evolution, guide degraded soil remediation, and support the sustainable development of regional ecological agriculture.