In recent years, the Tanshan-Shangfu Nb-Ta-Li-Be metallogenic prospective area has been predicted in the southern of Jiuling area, northwest Jiangxi Province. Mineralization types include granite-type and aplite-type. Study on the formation age and genetic mechanism of rare metal deposits, is the key points of the enrichment and mineralization of rare metals in Jiuling area. Based on the study of the columbite-group minerals U-Pb geochronology, petrography and petrogeochemistry, to determine the diagenetic age and mineralization age, rock formation and magma source characters of the Nb-Ta-bearing aplite, and make analysis on its metallogenic potential. The LA-ICP-MS niobite-tantalite U-Pb dating yields an age of 142±1 Ma, suggesting that the Nb-Ta-bearing aplite was formed in the Early Yanshanian period. The aplite is characterized by rich silica, alkali and aluminum, poor titanium and ∑REE, the wide range of Rb/Sr, and there exists obvious enrichment of niobium-tantalum-lithium-rubidium, and CaO/(K₂O+Na₂O)≤0.10, Al₂O₃/TiO₂＞160, high differentiation index. The REE diagram shows rightward incline and obvious negative Eu abnormity. The spider diagram of trace elements shows left side is uplifted and right side is gentle. All of these indicate that the aplite show features of highly differentiated S-type granitoids. It may be that the metamorphic argillaceous rocks of the Neoproterozoic Shuangqiaoshan Group in the Jiuling area were partially melted to form granitic magma, which during the transition stage from syn-collision to post-collision, and then to form highly fractionated aplite. In the late stage of magmatic differentiation and evolution, the interaction between fluid and melt leads to the enrichment of metal ore-forming elements like Nb-Ta-Li in the highly fractionated aplite. The Dongcao Nb-Ta-bearing aplite and the Nanling Nb-Ta-bearing granite, the Dahutang Nb-Ta-bearing granite porphyry have similar geochemical characteristics. Which is regarded as the main metallogenic geological body in the Tanshan-Shangfu Nb-Ta-Li-Be metallogenic prospective area.