The sintering behavior and electrical property of $Ce_{0.8}Gd_{0.2}O_{1.9}$ ceramics were investigated with the iron oxide concentration ranging from 0 to 5 mol%. Both the sintered density and grain size were found to increase up to 2 mol% $Fe_2O_3$, and then to decrease with further additions. At a higher $Fe_2O_3$ content above 3 mol%, grain size decreased by a pinning effect induced by different shape grains. The electrical conductivity was also increased with increasing $Fe_2O_3$ content up to 2 mol%. Total conductivity of 2 mol% $Fe_2O_3-added$ specimen showed the maximum conductivity of $2{ imes}10^{-2}{Omega}{cdot}cm^{-1}$ at $500^{circ}C$. The addition of $Fe_2O_3$ was found to promote the sintering properties and electrical conductivities of $Gd_2O_3-dope;CeO_2$.