The hydrolysis and condensation of cycloalkyltrialkoxysilanes as cyclopentyltrimethoxysilane and cyclohexyltrimethoxysilane have been studied in the presence of acid and base catalyst. The cycloalkyltrialkoxysilanes underwent both reactions in step by step to give cycloalkylsilanepolyols and their condensation products. Cycloalkylsilanetriols were obtained as powders in good yields (80-90%) by the hydrolysis of cycloalkyltrialkoxysilanes in acidic aqueous solution (pH ≒3.5). Cycloalkylsilanetriols are soluble in water and undergo easily the condensation to various polysilsesquioxane products under thermal, acidic or basic conditions. The characterization of cycloalkylsilanetriols and polysilsesquioxane products were carried out using ¹H, ¹³C, ²⁹Si NMR, IR, GPC techniques. We will discuss the chemistry of cycloalkylsilanepolyols and their condensation in details.