0.2PZN-0.8PZT　piezoceramics　have　been　prepared　by　a　conventional　mixed　oxide　method　and　the　two-step　calcination　process.　The　corresponding　microstructure　and　AC　impedance　spectrum　have　been　investigated.　The　results　reveal　that　the　specimens　prepared　by　both　methods　show　a　complete　perovskite　structure.　However,　the　microstructures　of　the　specimen　prepared　by　the　two-step　calcination　process　are　more　homogeneous　and　the　grain　sizes　are　increased　greatly.　Meanwhile,　the　relaxation　time　region　of　these　specimens　shows　a　broader　feature　compared　to　the　specimens　prepared　by　a　conventional　mixed　oxide　method　in　the　same　impedance　test　temperature　area,　which　suggests　that　relaxor　behavior　has　been　enhanced.　In　addition,　temperature　dependence　of　bulk　relaxation　time　is　found　to　obey　linear-Arrhenius　fit　for　specimens　prepared　by　both　methods.　The　calculation　results　indicate　that　the　specimens　prepared　by　the　two-step　calcination　process　have　the　larger　activation　energy　values,　which　correspond　to　the　lower　concentration　of　oxygen　vacancies.