With chemical analysis and X-ray diffractory(XRD),the chemical compositions and phases evolution of Ti(CN) base cermets debinded in H2 or in vacuum and then sintered in vacuum were studied. The total carbon of cermets debinded in H2 was lower than that debinded in vacuum by 0.4 %~0.5 %. The contents of carbon and oxygen were decreased sharply at 1 100~1 300 ℃ and the decomposition peak of nitrogen appeared at 1 300 ℃. When the appearance of liquid phase，the decomposition of nitrogen was inhibited, and the decomposition of nitrogen began again when the sintering temperature above 1 500 ℃. TaC and Mo2C began solution reaction at 900 ℃ and disappeared at 1 200 ℃. WC disappeared at 1 300 ℃. Keywords ：Ti(CN) ；cermets；sintering；composition；phase