Effects of B4C and C additives on the densification behavior, phase composition, and microstructure of TiB2 ceramics were studied. The relative density of pure TiB2 ceramics by hot pressing at 2000°C for 1 h was only 77.4%. With the introduction of B4C and C additives, the relative density increase to 97.4% and 98.1%, respectively. The great improvement on densification was due to the removal of surface oxides of TiB2 powders by reaction with B4C and C additives. Microstructure observation showed the addition of B4C led to some TiB2 grains abnormal growth (>10 µm), whereas the addition of C produced a uniform and fine-grained microstructure.