Polycrystalline thin films of BaTiO3 were deposited on fused quartz substrates at 600°C by metalorganic chemical vapor deposition (MOCVD). The films were characterized by x-ray powder diffraction (XRD), transmission electron microscopy (TEM), secondary ion mass spectroscopy (SIMS) and Raman spectroscopy. Films prepared in the early stages of this study that had appeared to contain only crystalline BaTiO3 by XRD were found to have nonuniform composition and microstructure through the film thickness by SIMS and TEM. The MOCVD system was then modified by installing a process gas bypass apparatus and an elevated pressure bubbler for the titanium isopropoxide precursor. A 1.2 μm thick BaTiO3 film prepared in the modified system demonstrated much improved compositional and microstructural uniformity through the thickness of the film. This film had a columnar microstructure with grain widths of 0.1–0.2 μm and exhibited tetragonality as detected by Raman spectroscopy.