The Shanhu tungsten-tin deposit, which is located in the middle part of the Fuchuan-Hezhou-Zhongshan W-Sn-polymetallic metallogenic province, northeastern Guangxi, is a typical hydrothermal quartz vein type deposit in the Nanling metallogenic belt. In this paper, both40Ar-39Ar age of muscovite and Rb-Sr isotopic age of fluid inclusions in quartz vein are reported for this deposit. The muscovite40Ar-39Ar yields a plateau age of 101.7±0.7 Ma (MSWD=0.34) (with isochron age of 102.0±1.0 Ma, MSWD=1.17), which is consistent with the Rb-Sr isochron age of 106.4±3.5 Ma (MSWD=0.83) for the fluid inclusions. These ages show that this deposit is part of the extensive late Yanshanian magmatism and mineralization in the South China. Through preliminary analysis of fluid inclusions in quartz, we suggest that a “re-equilibrated magmatic water-hydrothermal” ore forming fluid for this deposit. Mineralization regulation drawn from this study can provide guidance for exploration in the areas of such kind, and thus of great significance.