Abstract: Ti-54Al-xB alloys have been produced by an in-situ method. The microstructure and phases constituent of these alloys were investigated by XRD and SEM. The results show that there are needle shape dendrites which are parallel to [0001] on the edge of TiB₂ plate and convex flakes which are perpendicular to [0001]on the surface of TiB₂ plate. These needles or flakes exhibit facets parallel to those of TiB₂ plate. It was analyzed that the Al rich layer and inhomogeneity in supersaturation at the solid-liquid interface resulting from non-equilibrium solidification may make the solid-liquid interface unstable, and lead TiB₂ plate to forming the surface structure.