Nano-sized TiN powders with an average particle size of 19 nm were synthesized via a new method, reduction-nitridation reaction in liquid ammonia. A consolidation procedure using spark plasma sintering (SPS) was used, and a dense TiN ceramic ( > 98% of theoretical) with mean grain size of 100-150 nm was obtained at 1380 degrees C. The influence of sintering temperature on grain growth and microstructural evolution was also discussed.