The deposited microstructure of SLM TC4 constitutes coarse β columnar crystals with martensite α′ and α″ as the intragranular substructures. The microstructure of SLM TC4 after solution aging heat treatment is bimodal, and a secondary α phase is generated during the aging process. During the cyclic annealing process, parts of the grain boundary α phase and lath α phase are broken to form an equiaxed α phase. After the cyclic spheroidizing annealing and solution aging treatment, the microstructure of the sample is mainly composed of the lath α phase, equiaxed α phase, and secondary α phase; the volume fraction of the equiaxed α phase is relatively high. The standard deviation of the mechanical property data of SLM TC4 is generally large, which is significantly reduced after the heat treatment. The strengths of the samples treated either solely by solution aging or a combination of cyclic spheroidizing annealing and solution aging are roughly equivalent. The sample plasticity obtained by the combined cyclic spheroidizing annealing and solution aging is better than that obtained by solution aging alone. After the heat treatment methods, the mechanical properties of the samples exceed the national forging standard. The plastic anisotropy of SLM TC4 depositions is high. However, the three heat treatment processes significantly reduce the plastic anisotropy. Among these processes, the solution aging treatment provides the deposited TC4 with the lowest anisotropy of the mechanical properties. SLM TC4 depositions have mixed fracture morphology, while the deposited TC4 after heat treatment shows a typical ductile fracture.