ＰｂＴｉＯ３ thin films were deposited on (001) redoping n-Si, (001) SrＴｉＯ３ substrates by low-pressure MOCVD technique, XRD θ－２θ scan shows that the film on Si substrate has a polycrystalline structure, while the other two films have preferential orientations and their epitaxial nature was confirmed by the X-ray φ scan, rocking curves of the two epitaxial thin films were taken at BSRF using the synchrotron radiation. The film on LaAlＯ３ substrate has an a,c domain coexisting structure, and the film on ＳｒＴｉＯ３ substrate only has a c-orientation. All the films exhibit a c-axis shortening compare with the bulk material, and the reason can be attributed to the size effect and surface influence. The ferroelectric properties of the polycrystalline thin films were investigated using the redoping Si substrate as bottom electrode directly, and the ＰｂＴｉＯ３ thin film shows a perfect hysteresis loop.