Abstract:The effects of NiO/Ni2O3 doping amount on the phase structure, microstructure and electrical properties of BaNiⅡxBi1-xO3 and BaNiⅡx/3NiⅢ2x/3Bi1-xO3 (x=0.02~0.08) based thermosensitive ceramics were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) and ρt characteristic tester. The results showed that with the increase of the NiO/Ni2O3 doping amount, the roomtemperature resistivity ρ25and the thermal constant value B25~85 of the ceramic sample first decreased, and then increased again. The excellent thermosensitive properties were achieved for BaNiⅡ0.04Bi0.96O3 ceramic with ρ25 =2 743 Ω·cm and B25~85 =3 239 K. For BaNiⅡ0.02NiⅢ0.04Bi0.94O3 ceramic, the optimal values of ρ25 and B25~85 were 65 Ω·cm and 2 673 K, respectively.