Dilatometer analysis was conducted for nano-CeO 2 particles, with varying green densities. Bimodal shrinkage rate was noticed for nano-particles with respect to temperature, while single mode was observed for submicron particles. With decrease in green density, the intensity of the low temperature peak in the bimodal shrinkage rate increased compared with that of high temperature peak. The activation energies of nano-CeO 2 sintering estimated by the master sintering curve were 370 and 440kJ/mol for temperature ranges near the low temperature peak and near the high temperature peak, respectively, while the activation energy of submicron-CeO 2 sintering was 420kJ/mol. It was found that the low temperature peak characterized the sintering behavior of nano-CeO 2 , and this peak was responsible for the enhancement in the sinterability of green compact with low density.