Abstract: Greisen-type Li ore, a new type of lithium ore in recent years, is of great theoretical research and economic value. However, there is slightly insufficient in comprehensive evaluation of greisen-type Li ore in such a world-class Nanling W-Sn metallogenic province and its surroundings. In this work, we found greisen-type Li mineralization firstly in the Yanbei Sn-ore field, Huichang district, Jiangxi Province. The lithium mineralization occurred at the greisen belt near the contact zone between the Minkengshan granitic batholith and overlying volcanic rock of the Jilongzhang Formation. Three types of mineralization were identified: the greisen type, the quartz vein type in granite, and the quartz vein type in volcanic rock. The content of Li₂O reaches 1.04% and mainly ranges from 0.2%−0.3%, which is of significant comprehensive utilization value. The occurrence state of lithium and the metallogenic characteristics based on the detailed microscopic observation, scanning electron microscope (SEM) images, electron probe microanalysis (EPMA) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) is determined here. There is a potential difference between the Yanbei ore field and other domestic and international typical greisen-type lithium deposits, which develop lepidolite-ferrolepidolite series. The main Li-bearing mineral is protolithionite in the Yanbei ore field, and it is identified as high Si, Al, K, Fe and Li with no significant extreme fluid differentiation process. The Li, co-accumulated with Sn in the post-magmatic high-temperature gas-liquid stage, can be linked to the porphyritic fine-grained granite and enter mica via coupling substitution of Si⁴⁺+Li⁺↔Al^Ⅳ+Fe^T.