Na0.5Bi0.5Cu3Ti4O12 (NBCTO) ceramics were prepared by conventional solid-state reaction method. The phase structure, microstructure and dielectric properties of NBCTO ceramics sintered at various temperatures with different soaking time were investigated. Pure NBCTO phase could be obtained with increasing the temperature and prolonging the soaking time. High dielectric permittivity (13,495) and low dielectric loss (0.031) could be obtained when the ceramics were sintered at 1000 degrees C for 7.5 h. The ceramics sintered at 1000 degrees C for 7.5 h also showed good temperature stability (-4.00 to -0.69%) over a large temperature range from -50 to 150 degrees C. Complex impedances results revealed that the grain was semiconducting and the grain boundaries was insulating. The grain resistance (R-g) was 12.10 Omega cm and the grain boundary resistance (R-gb) was 2.009 x 10(5) Omega cm when the ceramics were sintered at 1000 degrees C for 7.5 h. (C) 2010 Elsevier Ltd. All rights reserved.