The mineralization process of elution-deposited Rare Earth Element (REE) deposits is closely related to chemical weathering. Elution-deposited REE deposits in South China are an extremely important type of rare resource, with large reserves, a wide distribution, and a high content of Heavy REEs (HREE). In recent years, the migration and enrichment mechanism of earth elements during the chemical weathering process and the ore-forming mechanism of elution-deposited REE deposits has garnered great research interest. This subject has become one of the central issues in geoscience research. Multiple aspects, such as the metallogenic characteristics and processes of elution-deposited REE deposits, structural characteristics of granite weathering crust, distribution characteristics of REEs, occurrence and migration modes of REEs, main factors affecting the migration and enrichment of REEs, and the characteristics of Eu and Ce anomalies are systematically summarized in this paper. The purpose of this study is to comprehensively summarize knowledge centered on the behavior of REEs in the process of supergene weathering, to provide novel directions for future research. Non-traditional stable isotope tracing of chemical weathering is novel and effective; specifically, stable isotope analysis methods for Ce and Nd have been successfully established. Therefore, future research should explore earth elements through the lens of isotopic methods, as this approach could provide important insights for tracing chemical weathering, revealing the mineralization process of REE deposits, and studying environmental evolution.