BaTiO 3 based ceramics (with some additives such as ZrO 2 , SnO 2 , etc.) were prepared by solid state reaction. Mn 2+ or Mn 3+ as an acceptor substituting for Ti 4+ in B site and Bi 3+ as a donor substituting for Ba 2+ in A site were co-doped in BaTiO 3 based ceramics. The dielectric properties of BaTiO 3 based ceramics co-doped with Bi/Mn were investigated. The results show that the dielectric properties of BaTiO 3 based ceramics co-doped with Bi/Mn are affected by the mole ratio of donor and acceptor (Bi/Mn). When the mole ratio of donor and acceptor is high, dielectric dispersion behavior was observed and the dielectric constant decrease and remnant polarization, coercive field and piezoelectric constant will varied. When Bi varied from 1.0% to 2.0mol% (Mn=0.8mol%), remnant polarization from 10.35 to 2.25μC/cm 2 , coercive field from 4 to 2.75kV/cm, and piezoelectric constant d 33 from 137 to 36pC/N respectively.