Relaxor-based lead-lanthanum-zirconate-titanate (PLZT) thick films were prepared on Ti substrates by a simplified hydrothermal method, in which the precursors were heated to 150 oC with durations from 8 to 32h. The mixture of oxides was used as the staring materials. The smooth PLZT films with a single perovskite structure were obtained through the synthesis route. Structural and morphological studies were carried out on hydrothermally synthesized films. The influences of the mineralizer concentration on the structural, morphological, and physical characteristics of the particles are studied. Phase characterization and crystal orientation of the PLZT thick films were investigated by x-ray diffraction analysis (XRD). The dielectric constant and dielectric loss of the PLZT thick films were measured. In the frequency range from 1000 to 100 MHz, the dielectric constant and the dielectric loss were very steady.