Leaching of uranium-fertile granites represents a major source of uranium, as uraninite is easily dissolved in oxygenated aqueous solutions. This phenomenon is well documented at surface conditions, but remains poorly documented for granites at depth. In this study, we propose that surface-derived oxidized hydrothermal fluids leached uranium from uraninite in the Questembert peraluminous granite at temperatures greater than ~70° to 160°C. This Variscan synkinematic granite is characterized by widespread and pervasive development of vertical and permeable C-S structures. These structures likely facilitated the infiltration of oxidized hydrothermal fluids from the surface, their circulation at depth, and the subsequent fluid-rock interaction in the granite. Published oxygen isotope data shows that it has undergone subsolidus fluid-rock interaction, dated between 312 and 303 Ma by 40Ar/39Ar analyses on muscovite. These interactions were responsible for the concomitant decrease of the feldspar