Simple cycloalkylsilanetriols RSi(OH)3 [R =c- pentyl (1</b>) and c-hexenyl (2b</b>)] were synthesized as white powders in 70% and 90% isolated yields, respectively, from the hydrolysis of the corresponding trialkoxysilanes with mild acidic water. Silanetriols 1</b>,2</b> are soluble in water and polar organic solvents such as alcohol, acetone, THF, DMSO, and etc. They can be applied as surface modifiers for inorganic materials such as silica and titania through simple two step processes: 1) organosilanetriol interact with hydroxyl groups on inorganic materials through hydrogen bonding to make molecular layered thin coating on the inorganic surface, 2) then can undergo condensation by heating about 110 ℃ above to form M-O-Si covalent bond to give hydrophobic silica. With the treatment of ca. 50 nm spherical silica with 5 wt % alkylsilaneol 1, no precipitation of silica particles in water was observed, indicating good surface modifiers for silica particle. In this presentation we will discuss the application of silanetriols as surface modifier for inorganic materials such as silica and titania particles.