Samarium-doped CeO2 (SDC) compounds are good candidates for application in intermediate temperature solid oxide fuel cells (IT-SOFCs), where appropriate densification would lead to increased grain and grain boundary conductivity. In the present work, SDC containing 20 and 30mol% samarium were prepared by a combined process of mechanical alloying and heat treatment. The dense sintered body was obtained by two-step sintering (TSS) and conventional sintering (CS) methods. The products were characterized by SEM, XRD and impedance spectroscopy in the temperature range of 400–700°C. TSS of the powders containing 20mol% samarium resulted in the enhancement of electrical conductivity and significant suppression of grain growth. Grain boundary resistivity was reduced with decreasing the grain sizes.