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The Greater Caucasus belt is the northernmost expression of the Caucasus orogen and is linkedto the southern margin of the Precambrian Scythian Platform. In the pre-Jurassic crystalline basementof this belt, a plagiogranite vein, exposed in the headwaters of the Enguri River, with elevated radiation(μSv/h range of ~1–3), has been discovered. The vein is located along the Main Thrust of the GreaterCaucasus, in the upper Paleozoic biotite migmatites of the Shkhara crystalline massif. It is ~2–3 m thick andrepresents hydrothermally altered rock (SiO2content varies from ~75% to ~85%) predominantly composedof a quartz-plagioclase assemblage. LA-ICP-MS206Pb/238U dating of zircons from the vein indicates an age of310.2±7.5 Ma that corresponds to the late Variscan orogenic activity. The vein is slightly fragmented andfractured, and fractures and nests are filled with Th-enriched uraninite veins and impregnations. Accordingto ICP-MS-ES analyses, the Th content varies from ~26 ppm to ~50 ppm, and the U varies between ~55 ppmand ~290 ppm. Based on the conducted research, it was found that there is a full correlation between thestudied vein and U-bearing granitic veins of different regions of the world by composition, magma series,geodynamic setting, tectonic location and isotopic age. On this basis, it is supposed that the late Variscanhydrothermally altered plagiogranite veins, which are localized in the shear zones of the Shkhara Massif, andentirely in the Main Range Zone of the Greater Caucasus, are potentially U-bearing.