In order to explore the stabilizing effect of solid particles on the emulsions, nano-silica was synthesized by using L-lysine as the catalyst, and was modified by hexamethyldisilazane in order to obtain hydrophobic performance. Pickering emulsions were prepared by nano-silica acting as stabilizer which was modified by HMDS. The preparation, surface modification of nano-silica and properties of Pickering emulsions were characterized by particle size analyzer, HRTEM, FTIR,TG-DSC, contact angle, optical microscope and electrical conductivity meter respectively. The results showed that the silica spheres with small particle size and uniform morphology were successfully synthesized, and the hydrophobic bond of trimethylsilyl was successfully grafted onto the surface of nano-silica. For Pickering emulsions prepared by different concentration of nano-silica, the stability of emulsions increased gradually with the increase of concentration of nano-silica. Meanwhile, the droplet diameter of emulsions decreased with the increase of concentration of nano-silica. Pickering emulsions prepared by different oil/water ratio, we can conclude the stability of the emulsions increased with the increase of oil phase volume to some extent.