Abstract: The mechanism of emission from ferroelectric cathode was introduced. With the purpose of obtaining the ferroelectric cathode material with large emission current density, the preparation conditions of PZT series ceramic were studied. By doping, modifying and some other methods of processing amelioration, the improvement of performance was observed in both ferroelectric and relaxor ferroelectric ceramic. In the preliminary experiment, with 5.4 kV external pulsed voltage, the electron emission density of PLZT8/65/35 reached up to 800 A/cm2, which was much greater than that calculated by C-L principle.