Ti46Al0.5Si0.5W alloys ingots directional solidified by cold crucible with flakiness ratio 2.5:1 are heat treated differently. The structure and mechanical properties of those ingots as cast and as heat treated are studied. The results show that heat treatment can change the structure and mechanical properties, appropriate heat treatment can refine grains and lamella, and homogenize structure. Grain will grow bigger when the ingots are heated above 1360℃, but will not change below 1150℃. Rapid heating cyclic heat treatment will refine structure and improve mechanical properties.