This paper investigates the structural controls of the Kadjaran deposit, the evolution of hydrothermal fluids with variable salinity, temperature and pressure, based on a detailed field mapping, petrographic and fluid inclusion microthermometry. Detailed structural mapping and interpretation of stereonets compiling ore-bearing fractures within stockwork and vein zones allow us to define the main ore-controlling structures and main orientations of veins of the different mineralization stages of the Kadjaran deposit. The ore-enriched areas are zones sub-parallel to eastwest-oriented fractures. In particular, they are located in areas where they crosscut steeplydipping (70-85°) eastwest-, northsouth- and northeastoriented fractures. Five types of fluid inclusions were distinguished according to their nature, bubble size, and daughter mineral content. Cathodoluminescence (SEMCL) images reveal four generations of quartz. Molybdenite is associated with a dark luminescent quartz generation (Q2), which contains typical brine and aqueous-carbonic fluid inclusions, with some of them coexisting locally as boiling assemblages. Final homogenization of all brine inclusions occurs by halite dissolution. Dissolution of halite between 356±8 and 422±10°C in brine (B1) inclusions of quartz - molybdenite veins indicates salinities between about 42.6 to 50.7 wt % NaCl equiv. The vapor bubbles homogenized between 278±4°C and 327±5°C.