Nanosize (Na0.5Bi0.5)(0.94)Ba0.06TiO3 precursor powders were prepared via the citric acid sol-gel method. The ceramics were sintered at 1100-1150 A degrees C. All ceramics exhibit a single-phase perovskite structure. With increasing sintering temperature, the average size of grains in the samples changes slightly from 0.3 to 0.5 A mu m. All ceramics show obvious dielectric dispersion. Activation energy values were obtained via impedance, electric modulus, and conductivity, respectively, which are in the range of 0.60-1.06 eV. Compared to ceramics synthesized by solid-state reaction method, the as-synthesized samples are fine-grained and have high depolarization temperature and excellent temperature stability of the piezoelectric constant (d (33)). The d (33) value of the sample sintered at 1120 A degrees C remains as high as 119 pC N-1 with increasing annealing temperature to 115 A degrees C, whereas the reduced amplitude of d (33) is only approximately 3%.