The microstructural characteristics and mechanical properties of laser melting deposited TC11 titanium alloys are investigated by the reappearance of actual forming thermal process of large structural parts. The results show that, the α+β basket-weave microstructures in the coarse columnar grains of the as-deposited samples are more uniform and finer than those in the equiaxed grains. The large α colonies are found in the equiaxed grains and there are a lot of continuous α phases on the grain boundaries. Due to the interlayer surface remelting redeposition and annealing effects, the obvious coarsening of α phases occurs in the interlayer transition zone of as-deposited samples and the α phase proportion increases. As a result, the mechanical properties of as-deposited samples at room temperature exhibit an obvious anisotropy. After the double annealing under the schedules of 950 ℃, heat preservation for 1 h and 550 ℃, heat preservation for 2 h, the continuous α phases are nearly broken completely on the grain boundaries of the annealed samples, and the α+β basket-weave microstructures show a more uniform distribution. The anisotropy of the mechanical properties at room temperature is eliminated completely and the plasticity enhances considerably. The comprehensive mechanical properties are basically at the same level as those of the forged samples.