Gadolinium aluminum perovskite (GdAlO 3 , GAP) is a promising high temperature ceramic material, known for its wide applications in phosphors. Polycrystalline gadolinium aluminum perovskites were synthesized using a precursor of co-precipitate gel of GdAlO 3 by employing hydrothermal supercritical fluid technique under pressure and temperature ranging from 150 to 200 MPa and 600 to 700°C, respectively. The resulted products of GAP were studied using the characterization techniques, such as powder X-ray diffraction analysis (XRD), infrared spectroscopy (IR), scanning electron microscopy (SEM) and energy dispersive analysis of X-ray (EDX). The X-ray diffraction pattern matched well with the reported orthorhombic GAP pattern (JCPDS-46-0395).