Although the insulating oil filled is the surface of the PZT ultrasonic piezo plate quartz and the pore was removed after extraction, the hydrophobic is insulating oil component adhered to the surface and the pore, and the contact angle of pickup piezo transducer did not decrease significantly. As the plasma etching time increases, the hydrophilicity of the piezo ceramic membrane increases, piezo ceramic fabrication is indicating that the number of hydrophobic groups is attached to the surface of the piezo ceramic membrane gradually decreases. When the etching time is 4 min, the hydrophilicity of the piezoelectric pressure sensor is basically restored and the contact angle is 16 °. Because the plasma etching can only deal with the surface groups of the membrane, the hydrophobic groups of PZT material piezo crystal present in the pores prevent the water droplets from infiltrating the pores. The mass of PZT ceramic membrane obtained is at 4 min after unpolarized, pzt material stress sensor is polarized, extracted, and plasma etched, the resonant amplitude at 20 V AC, and the permeability of pure water is at 0.05 MPa were similar to those of nitrogen permeation rate measurement results.Porous PZT ceramic membrane after ethanol extraction, and then plasma etching 4 min after the nitrogen permeability can be restored to , pure water permeability returned to MPa-1, the resonance signal of conical piezoelectric transducers is 34.8 mV. The resonance curves of PZT ceramic after polarization and extraction are given. The extracted porous PZT piezo ceramic wire leads membrane resonance signal is 34.8 mV, slightly lower than that of the PZT ceramic membrane after the polarization, which is caused by the space dissipation of the ultrasonic wave generated by the vibration in the pores of the extracted porous PZT ceramic membrane. The ultrasonic loss in the porous PZT ceramic membrane can be compensated for by increasing the AC voltage across the PZT ceramic membrane.