TiO2 nanoparticles with excellent photocatalytic and degradation property were prepared in the solvothermal method. They were characterized by the means of the transmission electron microscopy (TEM), the X-ray powder diffraction (XRD), the thermogravimetric analysis and differential thermal analysis (TG-DTA), the Fourier transform infrared spectroscopy (FT-IR) and nitrogen adsorption. The photocatalytic and degradation property for the methyl orange aqueous solution was researched. The results showed that as-prepared TiO2 nanoparticles were spherical crystals, and the particle size was about 10 nm. They had integrated crystal form, high crystallinity and thermal stability. The adsorption-desorption isotherms of TiO2 particles corresponded to the typical type IV isotherm, which is a clear N2 hysteresis loops of type H4 in the desorption branch. The average pore size was 3.572 nm, the specific surface areas was 203.245 m2/g. Moreover, the obtained TiO2 particles had perfect photocatalytic and degradation property for the methyl orange aqueous solution. When reacted for 150 min, the degradation rate of the methyl orange aqueous solution was at the peak, up to 99.1%.