Abstract: Selection of kyanite pure mineral as the research object,relationships between crystal structure and surface properties of kyanite and their impacts on flotation were studied to provide theoretical guidance for the flotation process for effective separating kyanite.The results show that the strength of chemical bond Mⁿ⁺-X^n-:Si-O>Al-O.After the dissociation of kyanite,lots of Al³⁺ with unsatisfied valences and coordination valence are exposed on the surface of kyanite mineral.Zero isoelectric point is relatively high in aqueous solution,showing that the use of sodium dodecyl sulfate in a strongly acidic environment as collector flotation is very effective while sodium oleate is better as collector in moderate and strongly alkaline environment.