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Laser shock peening can enhance fatigue, wear and corrosion resistance of metallic components by generating high-amplitude and large-depth compressive residual stresses on their surface. In our work, a pulse laser with different energies of 20J, 25J and 30J has been employed to peen TC17 titanium alloy. Microstructure evolution of 25J laser shock peened specimen was examined by OM, SEM and TEM. Surface morphology and roughness of 20J, 25J and 30J laser shock peened specimen were studied by confocal laser scanning microscope. Residual stresses of 20J, 25J and 30J laser shock peened specimen were measured based on incremental hole drilling method and ESPI technique. The effects of 20J, 25J and 30J LSP on room temperature tensile properties were further analyzed. Results showed that the average α grain size reduced from 11.17 μm to 6.93 μm after 25J LSP. High density of dislocations and mechanical twins were observed with dislocation density increasing from 8.11×10₁₃ m_-2 to 3.59×10₁₄ m_-2. Surface roughness decreased from 0.922 μm to 0.537 μm and further decreased to 0.305 μm, while surface residual stresses increased from -213 MPa, to 296 MPa and further increased to -774 MPa after 20J, 25J and 30J LSP, respectively. After LSP, the yield strength increased by a value of 30 to 70 MPa and the morphology of the tensile fracture before and after LSP were both ductile fracture, which indicated that LSP induced grain refinement only had a slight effect on the tensile property of TC17 titanium alloy.