MgO thin films were deposited on SiO2/Si(100) substrates by a modified electrostatic spray pyrolysis (ESP) method using Mg(tmhd)(2) as a precursor source. In this modified ESP system, a guide, guide heaters, and an extraction electrode were added to the conventional ESP system, which has been widely used to synthesize sub-micrometer and nano-sized particles of oxidic materials. The growth rates of the films were changed from 34 to 87 Angstrom /min depending on the substrate and the guide temperature. The MgO films deposited at temperatures as low as 400-500 degreesC exhibited a (100)-preferred orientation even without a post-annealing treatment. No impurities were incorporated in the films within the detection limit of X-ray photoelectron spectroscopy analysis.