Nanocrystalline TiO_2 was used as an efficient and recyclable catalyst for the chemoselective trimethylsilylation of primary and less hindered secondary alcohols and phenols with hexamethyldisilazane(HMDS).All reactions were performed under mild and completely heterogeneous conditions in good to excellent yields. Nanocrystalline TiO 2 was used as an efficient and recyclable catalyst for the chemoselective trimethylsilylation of primary and less hindered secondary alcohols and phenols with hexamethyldisilazane (HMDS). All reactions were performed under mild and completely heterogeneous conditions in good to excellent yields.