Laser deposition technology and weld additive manufacturing technology are used to repair the laser deposition manufactured TC4 titanium alloy with defects, and then different heat treatments are carried out. Microstructures and mechanical properties of two kinds of repaired specimens are analyzed before and after heat treatments. The results show that there is dense metallurgical bonding between repaired zone and the substrate, and there is no obvious heat affected zone. In the laser repaired zone, prior columnar beta grain extends from the substrate to the top of repaired zone and the whole structure is almost same. In the weld repaired zone, there are huge equiaxed beta grains, the transgranular alpha phases are longer than alpha phases in the substrate. The strength and plasticity of laser repaired specimen are higher than those of TC4 forging standard. The strength of the weld repaired specimen is similar to that of the laser repaired specimen, but the reduction of area of the former is lower than that of the latter. The annealing heat treatment has little effects on microstructure and mechanical. The solution and aging treatment can coarse the alpha phase obviously and promote the plastic sharply of the specimen, and it has slight effect on strength, so the specimen can obtain good strength and plasticity. The two kinds of repaired specimen in heat treatment state have different tensile fracture mechanisms. The fracture surface of laser repaired specimen is covered with big and deep dimples, and the fracture shows ductile characteristics. The weld repaired specimen exhibits quasi-cleavage fracture with slight necking fracture, and shallow and flat dimples.