When repaired by laser forming repair, there generates tensile residual stress and bulky grains in the repair zone of titanium alloy components. Meanwhile, microstructures and performances are ill-distributed between the repair and matrix zone. Due to all above, fatigue strength of the repaired components is reduced seriously. Laser shock processing is adopted to treat the specimens which are repaired by laser cladding. The effect of laser shock processing on fatigue strength of the repaired specimens is researched. Mechanism of the effect is demonstrated by residual stress and microstructure analysis. The results suggest that fatigue limit of the matrix specimens is 401 MPa, but that of the laser cladding specimens is 365 MPa, which decreases by 9%; while treated by laser shock processing, fatigue limit of laser cladding specimens is improved up to 450.80 MPa, which increases by 23.5% . Considerable compressive residual stress is introduced by laser shock processing in the material surface, and depth of it reaches at 430 μm. Moreover, microstructures and performances are well-distributed. Compressive residual stress and improved microstructures are the reasons for that fatigue strength is enhanced.