High strength with high ductility can be achieved in the titanium alloys by using metal precipitated ceramic particle as reinforcement. In this work, alpha + beta or beta-Ti alloy composites were prepared with alpha-Ti precipitated TiC particles. A series of Ti-Fe-C-N alloys were prepared and a constitutional diagram was constructed as a function of N and Fe contents. Two criteria were identified for the formation of alpha-Ti precipitation. One is the existence of Ti2C phase and the other is the presence of alpha-Ti phase in the matrix. The mechanism of alpha-Ti formation from the Ti2C phase is discussed.