Rhombic TiO₂ nanocrystallines,10～15nm in diameter and 112m ²/g in specific surface area,were prepared from P25 via the hydrothermal method.Then,porous TiO₂ film was made from the nanocrystallines and were characterized by using a SEM and a N₂ adsorption unit.The results were compared with those of the film made from P25.It is found that the TiO₂ film is of narrow size and good dispersivity,and that its BET specific surface area and dye adsorption are both two times that of P25 film.Moreover,by analyzing the photoelectric properties of the dye-sensitized solar cells,it is concluded that the cell based on TiO₂ film is superior to that based on P25 film because the former is of high photocurrent density and conversion efficiency.