Lode gold deposits commonly consist of pyrite and lesser amounts of lead and zinc sulfides accompanied by quartz and calcite. Their exact origin remains controversial mainly because of the scarcity of reliable geochronological data. Here we present direct Rb-Sr dating of pyrite from a lode gold deposit and propose the method as a useful geochronological technique for gold mineralization for which age data are poor. A positive correlation between present-day 87Sr/86Sr and 87Rb/86Sr ratios of pyrite (FeS2) subsamples from the Linglong gold mine of China corresponds to an age of 122–123 Ma, which dates the age of gold mineralization. The Sr, Nd, and Pb isotopic compositions of pyrites and the associated rocks suggest that the hydrothermal fluids responsible for the pyrite and gold mineralization were probably derived from a mixed source (i.e., degassing of mafic magmas and meteoric water that had leached the country rocks).