Barium holmium zirconate, a new complex perovskite ceramic oxide, has been synthesized through liquid-phase sintering for the first time. The conventional solid-state reaction method using constituent oxides and carbonates was found to be inadequate for the synthesis of Ba2HoZrO55 material. During high-temperature annealing, the development of stable BaZrO3 and BaHoO2.5 phases prevented the formation of Ba2HoZrO5.5 as a single-phase material, even at 1650degreesC. However, an addition of a small amount of CuO (1 wt%) in the reaction mixture has resulted in the formation of an ordered complex perovskite Ba2HoZrO5.5 phase during the heating process. The structure of Ba2HoZrO5.5 was studied by X-ray diffraction and found to have a cubic perovskite structure with a lattice constant of a = 8.482 Angstrom Dielectric constant and loss factor values of Ba2HoZrO5.5 are also in the range suitable for use as a substrate for microwave applications. The X-ray diffraction and resistivity measurements have shown that there is no detectable chemical reaction in YBa2Cu3O7-delta-Ba2HoZrO5.5 and Bi(2212)-Ba2HoZrO5.5 composites, even under extreme processing conditions. Dip-coated and melt-textured YBa2Cu3O7-delta and Bi(2212) thick films developed on polycrystalline Ba2HoZrO5.5 gave zero-resistivity transition temperatures of T-c(0) = 92 and 85 K, respectively.