The work aims to adjust parameters to obtain good mechanical properties of material surface in view of the effect of laser shock wave propagation mode on the residual stress distribution of 7050 aluminum alloy under the Gaussian laser. The finite element software ABAQUS was used to simulate the effect of spherical wave and plane wave on residual stress distribution of 7050 aluminum alloy by changing the diameter of laser spot. X ray residual stress detector was used to verify the simulation results. When the shock pressure was 2 GPa, the spot diameter was 2 mm with spherical wave, and the spot diameter was 4 mm with plane wave. The shock pressure could change the propagation mode of the shock wave in the material. When the shock peak is 2 GPa, the spot with a diameter of 3 mm changed from spherical wave to plane wave, and when the shock pressure reached 3 GPa, the spherical wave completely transformed into plane wave. The effect of spherical wave on surface residual stress and residual stress in depth direction was smaller than that of plane wave, and the depth difference was 50 μm. The error between simulation results and test results was less than 15%, and the results are in good agreement. When 3 mm spot is used for shock, more uniform surface stress distribution can be obtained by reasonable use of the shock pressure on the propagation mode than that under the same conditions of flat-top laser, and the difference of the depth of the affected layer and the maximum residual stress is small.