Electrum-galena-sphalerite mineralization of the Jeoneui Au-Ag mine was deposited in three stages of quartz and calcite veins at temperatures between 350°and 180°C from moderate salinity fluids (4 to 14 wt%NaCI eq). Evidence of boiling indicates pressures of <150 bars, corresponding to depths of 700 and 1, 800m assuming lithostatic and hydrostatic loads. Au-Ag deposition was likely a result of boiling, coupled with declining temperatures. Sulfur isotope compositions of sulfides indicate an igneous source with a δ34S value near 4‰. Measured and calculated hydrogen and oxygen isotope values of ore-forming fluids suggest significant meteoric water involvement. Comparison of the Jeoneui Au-Ag deposits to similar shallow Cretaceous Au-Ag deposits and a deeper Jurassic Au system reveals an inverse relationship between depth and water-to-rock ratios in Korean Au-Ag vein deposits. This indicates significant differences in the postmagmatic evolutions of these granite-related gold-bear-ing hydrothermal systems and may be indicative of the manner in which Au and Ag are scavenged from cooling plutons.