the invention discloses a fluoride modified organic silicon nanometer paint, which consists of solvent and active component, wherein the active component is fluoride modified organic silicon nanometer particle, whose reacting raw material contains silicate ester, alkyl silane and fluoride modified alkyl silane according to 8-20: 0.5-1.5: 1. the preparing method comprises the following steps: first, preparing silica nanometer particle through hydrolyzing silicate ester; second, proceeding surface modifying through silica nanometer particle to prepare the product. |