A novel method of preparation of superhydrophobic nanosilica by surface-modification in situ in aqueous solution is reported in this paper. The silica nanoparticles modified by hexamethyldisilazane show Superior hydrophobic and excellent dispersive properties in organic solvents. Wettability Studies show that the film of nanosilica is superhydrophobic with a very large contact angle (167 +/- 2 degrees) and a small sliding angle (less than 2 degrees).