Pb(Ni1/3Nb2/3)0.72Ti0.28O3 (PNNT) perovskite ceramics produced by a reaction-sintering process were investigated. Without any calcination, the mixture of PbO, Ni(NO3)2, Nb O5 and TiO2 was pressed and sintered directly into PNNT ceramics. PNNT ceramics of 100% perovskite phase were obtained. For PNNT sintered for 2 h in PbO compensated atmosphere, maximum density reaches a value 8.49 g/cm3 (99.8% of the theoretical value) at 1250℃. Amaximum dielectric constant 20600 occurred around 37℃ at 1 kHz in PNNT sintered at 1250℃ for 2 h.