Abstract: Lead zirconate titanate (PZT) thin films with excess Pb were prepared by metal-organic decomposition process. The abnormal pinched P-E hysteresis loops and abnormal four peaks C-V curves were obtained for PZT films with excess Pb. Meanwhile the degree of abnormal electric properties of PZT thin films becomes more severe with time. The results can be explained by formation of PbO₂ phase at boundaries of crystalline grains and clusters, and at the interface between bottom electrode and film during annealing processl PbO₂ may induce trapped charges and acts as pinning centers, and has a strong effect on the ferroelectric domains. The degree of abnormal electric properties of PZT films is closely related with trapped charges at grain boundaries and interfaces.