The surface treatment of TC11 titanium alloys by lasers with different energy spatial distributions is conducted, and the residual stress in specimens induced by laser shock peening (LSP) is tested by X-ray diffraction. The results indicate that, under the same process parameters, the surface residual stress and the stress-affected layer depth in titanium alloys after LSP with a Gaussian distribution are -636.71 MPa and 1187 μm, respectively, while those with a flat-top distribution are -559.20 MPa and 811 μm, respectively. The theoretical calculation shows that the peak stress of shock waves induced by Gaussion spatial energy distributions is 1.55 times of that by flat-top spatial energy distributions.