Abstract: The study of the mechanism between minerals and reagent becomes a reality with the development of the molecular dynamics and the improvement of computing hardware. This paper introduces the molecular dynamics simulation and its application to the interaction between minerals and reagent， the behavior of reagent and the structure of minerals in detail. The macroscopic display that can not be done by traditional flotation method of flotation behavior can be achieved through the methods of molecular dynamics simulation in molecules perspective. The combination to the traditional flotation methods is the key points to the molecular dynamics simulation. The development of better force field and the connection to the quantum chemistry is the development direction of the molecular dynamics simulation.