In this study (Bi2O3)(0.9-x)(Tb4O7)(0.1)(Sm2O3)(x) ternary solid solutions were synthesized by solid-state synthesis techniques. The products were characterized by means of X-ray powder diffraction, differential thermal analysis/thermal gravimetry, and the four-point probe technique (4PPT). Total electrical conductivity (sigma T) depending on the temperature and doping concentration has been measured by 4PPT. Activation energy of the four samples are calculated by Arrhenius relation. Activation energies of the samples increases with the concentration of dopant Sm2O3. Bi2O3-based ceramic system doped with Sm2O3 and Tb4O7 showed an oxide ionic-type electrical conductivity which is increased with the increasing amount of Sm2O3. The highest conductivity value is found as 3.48x10(-1) S cm(-1) for the (Bi2O3)(0.85)(Tb4O7)(0.1)(Sm2O3)(0.05) ternary system at 850 degrees C.