In this study, piezoelectric materials 0.95 (Na0.5Bi0.5)TiO3-0.05 BaTiO3 (NBT-BT) composition with excess x wt% Bi2O3 (x=0, 1, 2, and 3) are investigated as a function of sintering temperatures. The sintering characteristics and dielectric characteristics of excess Bi2O3-doped 0.95 (Na0.5Bi0.5)TiO3- 0.05 BaTiO3 ceramics are developed with the aid of SEM, XRD patterns, and dielectric-temperature curves. The sintering process is carried out in air for 2h from 1120oC to 1200oC. Dielectric-temperature properties are investigated in the temperature range of 30oC~350oC at the frequencies of 10KHz~1MHz. The maximum dielectric constants of NBT-BT ceramics first increase with the increase of Bi2O3 content, reach the maximum at 1wt%- Bi2O3-added NBT-BT ceramics, and then decrease with the further increase of Bi2O3 content. The maximum dielectric constants of NBT-BT ceramics are almost unchanged as the measured frequency increases. The Curie temperatures of NBT-BT ceramics are also developed.