Phase-pure thin films of the YBCO, BSCCO, TBCCO lattice-matched and low dielectric-loss perovskite insulator PrGaO3 have been grown in situ on single-crystal (110) LaAlO3, (001) SrTiO3, and (001) MgO substrates by metalorganic chemical vapor deposition (MOCVD). Films were grown at temperatures between 750 and 800-degrees-C using the volatile metalorganic beta-diketonate precursors M(dpm)3 (M = Pr, Ga, and dpm = dipivaloylmethanate). As assessed by x-ray diffraction, the films grow epitaxially on LaAlO3 and SrTiO3 substrates with a high degree of (001) and/or (110) plane orientation parallel to the substrate surface. The films grown on MgO substrates are polycrystalline. Scanning electron microscopy reveals that the MOCVD-derived PrGaO3 films have smooth, featureless surfaces on all three kinds of substrates.