The magnesia ceramics were fabricated by atmospheric pressure sintering, which was using micro light MgO powder as raw material, Pr6O11 as additive and PVA as binding agent. Then the crystal phase, sintering properties, hardness, morphology and thermal shock resistance properties of MgO ceramics were investigated, which was obtained under sintering temperature 1580℃ and holding for 3h. The Pr6O11 was added to investigate the effect of different contents of RE oxides on sintering and thermal shock resistance of MgO ceramics. The results showed that the rare earth oxide had certain enhancement to thermal shock but little effect on the sintering properties. However, the hardness and thermal shock resistance of MgO were significantly enhanced, when the content of rare earth Pr6O11 was 8%, the optimal hardness and thermal shock resistance of MgO were 60.1HRA and 17times, respectively.