PZT films were deposited on the epitaxial Ir/(100)(ZrO2)(1-x)(Y2O3)(x)/(100)Si structures by sputtering. On the epitaxial (100) and the (100) + (111) Ir films, the tetragonal (001) PZT films were heteroepitaxially grown with a cube-on-cube relationship. Also, on the epitaxial (111) Ir film, the tetragonal (111) epitaxial PZT film was grown with quadruple domain. The crystalline quality of the epitaxial (001) PZT film was much better than that of the epitaxial (111) PZT film. The leakage and P-E characteristics of the epitaxial (001) PZT film on the (100) Ir film was superior to the (001) PZT film on the (100)+(111) Ir film and to the (111) PZT film.