Abstract: Phosphate ore is a strategic key mineral resource. China's phosphate ore reserves rank second in the world, mainly consisting of sedimentary phosphate rocks. Due to the fact that phosphate rock is an accumulation formed by exogenesis, composed of cryptocrystalline or microcrystalline apatite and other gangue minerals, and the surface wettability, surface electrical properties, and surface adsorption of apatite and gangue minerals are similar, making flotation separation difficult. Surface chemistry of flotation is an important theoretical basis for the flotation of phosphate ores and the key to achieving selective separation between different minerals. This article provides an overview of the crystal chemical characteristics and the surface characteristics such as the surface wettability, the electrical properties, and adsorption characteristics of the main useful minerals in phosphate rock, including apatite and main gangue minerals such as dolomite and quartz. It also discussed the changing characteristics of surface wettability under different flotation agents, the double layer structure of minerals in aqueous solutions, the active sites on mineral surfaces, and the adsorption configuration of collectors. On this basis, the influence of unavoidable ions on the flotation behavior of apatite and gangue minerals was summarized. It is expected to provide the theoretical support for the flotation separation of Medium−low grade phosphate ore.