PLZT(X/70/100) thin films on MgO(100), Pt/Ti/MgO(100), and Pt/Ti/Si(100) have been prepared by RF-magnetron sputtering process from sintered target with compositions of PLZT(X/70/100), where X=5, 10, and 15, respectively. The effects of substrate temperature, substrate and gas pressure on deposited thin films were studied. Crystalline and surface characterization was analyzed using XRD, SEM, AES, and AFM. X-ray rocking curves were measured to examine the film orientation. It was observed that the gas pressure was the dominant influence on having (001) preferred orientation. As a result, the degree of c-axis orientation increased as gas pressure decreased.