have been investigated. Generally, the compounds that contain PbO show p-type conductivity, because of PbO evaporation. Thus, the conductivities are known to be proportional to the PbO evaporation. However, PNN-PZ-PT ceramics exhibit a reciprocal relationship between the conductivities and the evaporation of PbO. Generally, no vacancy change is observed with the substitution of the same-charge valence ion. However, in the PNN-PZ-PT ceramic, lead vacancies could be created or annihilated by replacing Pb 2+ and Ni 2+ ions with Cd 2+ ions, because of incomplete substitution. The electrical conductivities are influenced by this incomplete substitution.