Strontium titanate films with high a-axis orientation [a(100)=94.1 % ] and random orientation were deposited on (111) Pt/Ti/ SiO2/Si substrates by a concentration controlling of the precursor solution during the metal organic deposition process. Topography of samples was investigated by atomic force microscopy after annealing at 800 °C. X-ray diffraction found that the degree of a-axis orientation increased with increasing annealing temperature. The leakage current and the dielectric property were strongly dependent on the film orientation, and the possible causes of orientation dependence were discussed.