Nanoceramic powders of n-type Ca0.95Sm0.05MnO3 (CSM) were synthesized by the coprecipitation method. Spark plasma sintering (SPS) technique was successfully used to densify granular n-type CSM oxides and control their nanostructure. Thermoelectric (TE) properties were measured and their dependence upon processing conditions was evidenced. SPS enables rapid sintering and better TE properties due to the strong densification and the grain size control. The power factor reached 306 μW·(m·K2)−1 at 600°C. These results contrast with those obtained by the conventional sintering (CS) method, where only 228 μW·(m·K2)−1 obtained at the same temperature. The mechanical properties of granular n-type CSM ceramics processed by SPS and CS were also investigated and compared.