Abstract: The Zhashanli fluorite deposit is a newly discovered super-large deposit in southern Jiangxi Province, and currently ranks as the largest of its kind in Jiangxi. Its discovery has challenged conventional understanding of the vertical extent of mineralization in similar types of fluorite deposits. Due to its recent identification, the deposit remains relatively understudied, and its metallogenic mechanism constitutes a key scientific question that demands further investigation. Based on extensive fieldwork, this study investigated the sources of ore-forming materials, metallogenic environment, and precipitation mechanisms of the deposit through integrated petrographic (ore microscopic) studies, whole-rock and ore geochemistry, H-O isotope analysis, and in situ trace element analysis of fluorite. The main findings are as follows: The mineralization of the Zhashanli fluorite deposit can be classified into two metallogenic periods and four mineralization stages. The two metallogenic periods are the hydrothermal mineralization period and the supergene oxidation period. The hydrothermal mineralization period is further subdivided into three stages: an early mineralization stage (fluorite-quartz-sulfide stage), a main mineralization stage (quartz-fluorite stage), and a late mineralization stage (fluorite-calcite-quartz stage). The H-O isotopic compositions indicate that the ore-forming fluids of the fluorite deposit were primarily derived from meteoric water and its thermally evolved geothermal water. In situ rare earth element (REE) analysis of fluorite demonstrates a hydrothermal origin, with mineralization precipitated from homologous coeval fluids under moderate-low temperature reducing conditions. Geochemical studies of major-trace elements and Nd isotopes in fluorite, wall rocks, and dikes reveal that: the ore-forming materials of fluorite were derived from the continental crust, with Ca predominantly sourced from Cretaceous clastic rocks and Nanhua metamorphic rocks, while F was mainly derived from deep-seated peraluminous calc-alkaline biotite granites. In this region, the radiogenic heat from deep-seated granitic intrusions, anomalous geothermal gradients, and Late Cretaceous intermediate-mafic volcanic activities collectively constituted the thermal sources for fluorite mineralization. In this region, radiogenic heat from deep-seated granitic intrusions, anomalous geothermal gradients, and Late Cretaceous intermediate-mafic volcanic activities collectively constituted the thermal sources for fluorite mineralization. The Zhashanli super-large fluorite deposit is classified as a paleo-geothermal circulation-related, shallow epithermal low-to-medium temperature hydrothermal vein-type fluorite deposit.