A thick-wall part of TA15 (Ti-6Al-2Zr-1Mo-1V) titanium alloy is prepared by laser rapid forming (LRF). The influence of annealing temperature on the microstructures and the tensile properties at room temperature of laser rapid formed TA15 titanium alloy is also investigated. Results show that the volume fraction of primary α lath inside coarse β grain decreases and that of the transformed β increases, and the pattern of the transformed β changes from lath (β)→layered tablets (α+β)→finer layered tablets (α+β) with the annealing temperature increasing. Results also show that after the heat treatment of 940 ℃/1 h, air cooling, the tensile properties of the formed TA15 alloy are optimal; when the annealing temperature is no less than 970 ℃, the tensile properties of the formed TA15 alloy decrease greatly, and the fractographs show that the tensile failures are brittle fracture.