Nano-sized TiO2 powders have been prepared by the sol–gel method under hypercritical conditions by hydrolyzing titanium tetra-isopropoxide. The polycrystalline structure and morphology of the powder have been characterized by X-ray diffraction (XRD), Fourier Transform InfraRed spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The XRD spectrum shows the anatase phase of the prepared TiO2 powder. The energy dispersive analysis (EDS) and FT-IR confirmed the formation of TiO2. TEM and SEM micrographs showed that the TiO2 grains are micrometric and have irregular shapes. These grains are formed by agglomeration of TiO2 nanocrystallites with an average size of 10 nm.