Poled Pb 0.99 (Zr 0.95 Ti 0.05 ) 0.98 Nb 0.02 O 3 ferroelectric ceramics in different porosity depoled under shock wave load. Porosity and material dielectric characteristic effects on the depoling current evolution were discussed. The results showed that under open circuit condition, the dielectric constant of all samples exhibited obvious increase, but as the porosity increased, the dielectric constant decreased. As a result of lower dielectric constant of porous samples during depoling process, the charge-releasing rate is faster than that of dense sample.