A series of experiments for growing epitaxial PbTiO 3 thin films have been made with radio frequency (r.f.) magnetron sputtering. The effects of various sputtering parameters such as substrate temperature, r.f. input power, gas composition, gas pressure and deposition rate on the chemical and structural characteristics of PbTiO 3 thin films were investigated. Highly c-axis oriented epitaxial ferroelectric PbTiO 3 thin films have been obtained under optimum sputtering conditions. The activation energy for the epitaxy formation was observed to be about 0.92 eV. The crystallinity of the epitaxial films was evaluated using rocking curve measurement as well as Rutherford backscattering spectrometry channeling measurement. The cross-sectional transmission electron microscopy study revealed that the c-axis oriented epitaxial film had 90° domain structures. The epitaxial relationship of the film was PbTiO 3 (001) MgO(001) and PbTiO 3 [100] MgO[100] in the c-axis oriented domain, its surface microstructure was highly mosaic. A good transparency in the region above 400 nm to infrared, and a remanent polarization of 34 μC cm - 2 and a coercive field of 97 kV cm - 1 were obtained.