In laser shock processing with circular laser spot, reverse plastic loading originating from the boundary of unaffected area will result in “residual stress hole” phenomenon. The “residual stress hole” phenomenon is proved by microhardness and residual stress test results of titanium alloy TC17, stainless steel 1Cr11Ni2W2MoV, aluminium alloy LY2 and Ni-based alloy K417 processed with single circular laser spot. Especially, the received effect laws of laser power density and impact times to “residual stress hole” phenomenon are studied. In order to reduce the influence of “residual stress hole” on the uniformity of strengthening, titanium alloy TC17 is chosen to study the optimized overlap rate and impact times. Results show that compared with single spot processing, with the same parameters, appropriate overlap rate and impact times could efficiently restrain the effect of “residual stress hole”. Particularly, with the overlap rate of 66% and impact times of three, the average value of microhardness and residual stress are increased by 60 MPa and 30 HV0.2, and the differences are reduced by 70 MPa and 94 HV0.2, respectively.