Abstract: Nano-titanium dioxide powder that has good dispersivity and small particle size was prepared by liquid-phase hydrolysis with the materials of titanium tetrachloride and n-octanol.The factors which influence the properties of titanium dioxide were researched by X-ray diffraction and transmission electron microscope.The results show: when the calcination temperature rises,the nano-TiO₂ particles become larger,and the dispersivity is worse;the crystal phase changes from anatase phase to rutile phase at higher temperature;the calcination time affects slightly on the nano-TiO₂ particle size and the crystal phase,but it affects intensely on the dispersivity of nano-TiO₂;when the titanium tetrachloride concentration increases,the nano-TiO₂ particle size becomes smaller,but the dispersivity becomes worse;and when the hydrolysis temperature increases,the nano-TiO₂ particle size becomes larger,and the dispersivity becomes worse.