A ternary carbide phase, namely Ti3AIC2, was successfully synthesized by not pressing (HP) and spark plasma sintering (SPS). Respectively, form the starting materisals of Ti, AI4C3 and activated carbon. The soaking temperature of HP process was 1400℃ and the soaking time varied from 5 to 120 min. The soaking temperature of SPS process was 1300℃and the soaking time varied from 1 to 7 min. Based on the results of X-ray diffractometer (XRD) and scanning electron microscopy (SEM), a possible mechanism was presented: firstly, at a certain sintering temperature, plenty of Ti6C octahedra depending on different soaking temperatures. One intermediate product is Ti6AIC obtained by linking every layer of Ti6C octahedra together by an aluminum plane. The other is TiC obtained by linling the Ti6C octahedra together directly. Finally, the intermediate products transform to Ti3AIC2 as the soaking time is extended, Ti2AIC loses half of its aluminum alyers and then transforms to Ti3AIC2. Ti6C octahedra in TiC crystals are separated by aluminum planes and then TiC transforms to Ti3AIC2.