Study on the Conductivity of ZrO_2--CaO(Y_2O_3) System Zhu Huiying;Lin Yunfei;Sun Shuzhen;Zhou XiangqinConductivities of CaO(Y_2O_3) stabilized ZrO_2 solid electrolyte have been studied using the com- plex admittance method in the present paper. With vary in stabilizer content there occurs a peak in the curve of the conductivity. And this can be explained relating to the coordination number(CN) of Zr in cubic structure during the stabilization of ZrO_2. The highest conductivity of ZrO_2-Y_2O_3 sys- tem is 19.10×10~(-2)Ω~(-1)·cm~(-1) and that of the ZrO_2-CaO system is 6. 284×10~(-2)Ω~(-1)·cm~(-1) at 1000℃. So doped ZrO_2 is a good oxygen ionic conductor at higher temperature.ZrO_2·CaO(Y_2O_3)system;;Eletrolyte;;Conductivity