Many primary,secondary,tertiary alcohols,and phenolic hydroxyl groups were effectively converted to their corresponding trimethylsilyl ethers using hexamethyldisilazane in the presence of catalytic amounts of tribromoisocyanuric acid and DABCO-bromine under mild conditions at room temperature with short reaction times in good to excellent yields.Excellent chemoselective silylation of hydroxyl groups in the presence of other functional groups were also observed. Many primary, secondary, tertiary alcohols, and phenolic hydroxyl groups were effectively converted to their corresponding trimethylsilyl ethers using hexamethyldisilazane in the presence of catalytic of tribromoisocyanuric acid and DABCO-bromine under mild conditions at room temperature with short reaction times in good to excellent yields .Excellent chemoselective silylation of hydroxyl groups in the presence of other functional groups were also observed.