Thin films of Lead Zirconate Titanate, $Pb(Zr_xTi_{1-x})O_3$(PZT), were grown on $Pt/SiO_2/Si(100)$ by metalorganic chemical vapor deposition(MOCVD). These films were analyzed with X-ray Phptoemission Spectroscopy(XPS) for determining their chemical composition and chemical bonding characteristics. It was found that the chemical compositions and chemical bondings of ions in the near surface are different from those in the bulk region of the films. The oxidation state of Ti ions in the bulk region is reduced in comparison to that of Ti ions ini the surface region of the films and Pb enrichment in the surface region was also observed. Pb ions in the surface region exists mainly in the form of $PbO_{ads}$(oxygen-chemisorbed lead), but Pb ions in the bulk region exists in the form of mixture of PbO and $PbTiO_3$