Abstract: Hydrothermal process is important for gold metallization. It is important significance that study being formal of gold in hydrothermal fluid.The most of discovered gold is native in natural world, and the size ranges is microfine or ultramicrofine.Gold can't be ionized by chemical reaction in natural.Synthetic gold complex is not finded in many geological circumstances.This paper proves that gold may be native in hydrathermal fluid on the basis of geological facts and nano-effects.