Maximum current density of 123A/cm2 has been obtained from PZT ferroelectric cath-odes in this study. The electron emission was driven by a high voltage pulsed generator, which supplied 150ns pulses. The ferroelectric samples were put in the vacuum cell and the exerting voltage was perpendicular to the polar dirrection. The effects of the material parameters on the electron emission from ferroelectric cathode. Such as the dielectric, piezoelectric and ferroelectric characteristics, were investi, The dielectric constant and the remnant polarizatin as well as the piezoelectric constant are all decreased, after the samples were tested by electron emission, this phenomenon is in conformity with the fast polarization theory. It has been proved that the emitted curent densities can by increased