Abstract: Piezoelectric ceramics（Na_0.5 Bi_0.5）_0.92Ba_0.08TiO₃ +x wt%MnCO₃ （BNBT-Mn）with x ranging from 0 to 1.6 were synthesized by conventional solid statereacti on.The sintered BNBT ceramics doped with proper amount of Mn exhibit a single-phase perovskit estructure.The amount of doped Mn in the ceramicshas great inf luence on dielectric constant （ε_r）,piezoelectric constants（d₃₃）and coercive field（E_c）.When 0.3wt%MnCO₃ is added,dielectric constant （ε_r）,piezoelectric cons-tants（d₃₃）reach the maximum value of 1850and 160×10^-12 C/N respectively.At the same time,coercive field（E_c）shows the relative low value,3.54kV/mm together with the improved temperaturestability.