Beryllium (Be) is widely used in advanced science and technology and strategic emerging fields, and is an urgent strategic resource for our country. The Tengchong terrane, which has experienced a complex geological structural process, is an important part of the East Tethys Orogenic belt. In this terrane, frequently magmatic activities occurred during the Cretaceous-Cenozoic stage and a large number of tin (tungsten) -rare metal deposits (mineralizatioin) related to magmatism have been discovered. Geological survey and evaluation indicate that potential beryllium, rubidium, niobium, tantalum rare metal deposits may be formed in this area. The Na"e beryllium deposit is a typical granitic pegmatite type deposit discovered in the Tengchong terrane. The granitic pegmatite intruded into the wall rock of the early Cretaceous monzogranite. In this paper, we study zircon U-Pb chronology of granite pegmatite and monzogranite (the wall rocks) and fluid inclusion of beryl and quartz from the granite pegmatite to discuss the ore-forming age and physical and chemical conditions of the Na’e beryllium deposit. LA-ICP-MS zircon U-Pb dating yield ages of granitic pegmatite are 44.3 Ma~46.9 Ma, that of monzogranite is 122.9 Ma, indicating that the Na’e beryllium deposit was formed in Eocene and the wall rock of monzogranite was formed in Early Cretaceous. Thus, we suggest that they have no evolutionary relationship. Combined with the magmatic activities and tectonic evolutionary history of the Tengchong terrane, we suggest that the Na’e beryllium deposit may be the product of crustal material melting in a post collision tectonic setting caused by the convergence between India and Eurasia plates, and is a typical LCT pegmatite type beryllium deposit at a post orogenic stage. Beryl and quartz from the Na’e beryllium deposit have vapor-liquid two-phase NaCl-H₂O inclusions and a small amount of pure liquid phase water inclusions and CO₂ inclusions. The ore-forming fluid is characterized by medium-low temperature (172.0 _o^C~299.4 _o^C), low salinity (0.70%~3.87% NaCl eqv.), and low density (0.723 g/cm_-3^{~0.913 g/cm}_-3^). According to the estimation of pressure and depth for ore-forming fluid, the Na’e beryllium deposit was formed in a low-pressure shallow environment. The concentration center of lithium and beryllium in geochemical anomaly map is consistent with the tin mineralization and pegmatite belts, suggesting that the rare metal mineralization is closely related to tin mineralization and pegmatite belt in the Tengchong terrane. In combination with the discovery of niobium, tantalum, rubidium, lithium mineralization in this district, we suppose that there is a potential for rare metal mineralization in the Tengchong terrane.