A model of the growth and morphology of Ti3SiC2 grains is presented in this work. In the growth of Ti3SiC2 grains, Ti6C octahedron can be recognized as an integrated growth unit and the linking modes of Ti6C octahedra (such as sharing planes, edges, or apexes) have strong influence on the growth behavior and morphology of Ti3SiC2 Some experimental phenomena such as preferred orientation of the {1 1 (2) over bar 0} plane in CVD method, and some hexagonal sections in the morphology of the fractured surface can be well interpreted using our model.