Barium zirconate (BaZrO₃) was prepared by a low-temperature composite-hydroxide-mediated (CHM) approach. The synthesis was performed using zirconium dioxide (ZrO₂) and barium hydroxide (Ba(OH)₂) as starting materials and a mixture of anhydrous hydroxides with NaOH and KOH as the reaction medium at 170–230°C for 18 h. Measurement by X-ray diffraction (XRD) confirmed the presence of perovskite BaZrO₃ particles and indicated that the lattice of the obtained BaZrO₃ was cubic. The amount of BaZrO₃ increased as the reaction temperature increased. Scanning electron microscopy (SEM) observation revealed that the BaZrO₃ particles were cube shaped, with side lengths of 50–240 nm and sharp-edged corners. It was found that small-scale BaZrO₃ cubes could be shaped from ZrO₂ and Ba(OH)₂.