Abstract: Mineral crystal properties and surface interface processes are the basis of mineral separation, purification and high performance materials. The influence of band structure and lattice defects on semiconductor properties of sulfide minerals is studied by density functional theory based on first principles, and a quantitative characterization method of lattice impurity activity is proposed. The structures of large-scale relaxation of sulfide mineral surfaces are simulated, and the model of surface catalysis and reduction of sulfide minerals is proposed. The hydration of sulfide mineralssur face is simulated, and the hydrophilic and hydrophobic models are established, which is beneficial to the flotation separation of minerals. The oxidation mechanism of sulfide minerals in water environment is investigated, and the mechanism and path of water-oxygen interaction are proposed. Galvani interaction at solid interface is simulated, and the quantum tunneling effect of electron transport at solid interface is discovered. Moreover, the interaction between gold and different minerals is studied.