TiO2 nanoparticle precursors were prepared by a sol-gel process using Ti(OC4H9)4 as raw material, and also were characterized by IR, XRD, TG-DSC. The results of infrared absorption spestra show that the acetate replaces the OR group and is directly bound to titanium hydrolysis while the pH=3. The alcohol condensation and dehydration condensation of precursors powder happened at 275 ℃, the weightlessness rate was 30%. The anatase to ruby crystal type steering occurred in 450 ℃. In 900 ℃ rutile content is about 90%, the anatase content is approximately 10%. The grain size is 18 nm in 400 ℃ and 21 nm in 900 ℃. The grain size becomes bigger with increasing temperature. Key words ：TiO2; sol-gel method; titaniumn-butoxide