Abstract: The Mineralization is referred to as all the processes of the origin, transport and precipitation of ore-forming matter. The ore-forming fluids are apparently very significant in the formation of ore deposits although not all of them can lead to the formation of ore deposits. The present paper deals in detail with the origin, dynamics, geochemistry and physicochemistry of the ore-forming fluids, in combination with the origin of ore-forming matter, gold behaviour in the ore-forming fluids, equilibrium and unstability-precipitation in the course of migration on the basis of mineral composition and mineralization, alteration and ore-controlling factors of the representative gold deposits hosted in the Ailao Mountains ophiolitic melange belt, Yunnan.