Two series of Ti(C,N) based cermet materials originating from the same chemical composition but with different grain size distribution and sintered to different stages of the sintering cycle have been studied using SEM, TEM, EDX, and XRD. Much of the surrounding structure is formed during solid state sintering. During the solid state sintering, at first, the Mo and W rich (Ti,Mo,W)C inner rim is formed by the interaction among TiC, WC, and Mo 2C; then the Mo and W lean (Ti,Mo,W)(C,N)outer rim is formed. During the liquid phase sintering, the outer rim of coarse grains grows rapidly throw a solution reprecipitation process; also coarse grains grow by particle coalescence. The interface between coarse grain outer rim and binder is flat (crystal surface). Two series of Ti (C, N) based cermet materials originating from the same chemical composition but with different grain size distribution and sintered to different stages of the sintering cycles have been used using SEM, TEM, EDX, and XRD. Much of the surrounding During the solid state sintering, at first, the Mo and W rich (Ti, Mo, W) C inner rim is formed by the interaction among TiC, WC, and Mo 2C; then the Mo and W W lean (Ti, Mo, W) (C, N) outer rim is formed. During the liquid phase sintering, the outer rim of coarse grains grows rapidly throw a solution reprecipitation process; also coarse grains grow by particle coalescence. The interface between coarse grain outer rim and binder is flat (crystal surface).