Ce1-xBixO2-δ(x = 0.00, 0.03, 0.05, 0.07, 0.10, 0.15, 0.30) solid solutions were synthesized via a hydrothermal method. The structure, spectra and electrochemical transport properties of the samples were characterized systematically. The powder X-ray diffraction analysis showed that all of the doped samples exhibited single phase fluorite structure. The particle sizes decreased from 18 to 9 nm and the lattice parameters increased gradually with the dopant content increasing from x = 0.03 to x = 0.30. The Bi3+ doping also induced the F2 g Raman peak to shift from 463 to 455 cm-1, and caused a red shift of the band gap energies calculated from UV-Vis spectra. The impedance plots at different temperature demonstrated that the boundary resistance was much larger than the grain resistance, and two activation energy values were obtained in different temperature range. Ce1-xBixO2-δ (x = 0.00, 0.03, 0.05, 0.07, 0.10, 0.15, 0.30) solid solutions were synthesized via a hydrothermal method. The structure, spectra and electrochemical transport properties of the samples were characterized systematically. The powder X- ray diffraction analysis showed that all of the doped samples exhibited single phase fluorite structure. The particle sizes decreased from 18 to 9 nm and the lattice parameters increased gradually with the dopant content increasing from x = 0.03 to x = 0.30. The Bi3 + doping also induced the F2 g Raman peak to shift from 463 to 455 cm-1, and caused a red shift of the band gap energies calculated from UV-Vis spectra. The impedance plots at different temperature demonstrated that the boundary resistance was much larger than the grain resistance , and two activation energy values ​​were obtained in different temperature range.