Fiber　laser　welding　is　an　effective　and　reliable　technology　for　thin-walled　structures　with　intensive　welds,　which　are　important　structures　in　aerospace,　ship,　and　rail　traffic,　etc.　However,　welding　of　such　structures　is　challenging　owing　to　welding　deformation　and　dimensional　shrinkage.　High-frequency　peening　was　conducted　during　welding　to　perform　related　experiments.　Thereafter,　the　effects　of　the　method　on　weld　morphology,　surface　stress,　welding　formation,　and　dimensional　shrinkage　were　systematically　studied.　A　self-built　experimental　platform　was　used　to　simulate　the　welding　of　a　thin-walled　structure　with　intensive　welds.　Further,　the　optimal　peening　position　was　obtained　in　the　high-temperature　weld　zone　in　the　trailing　end　of　a　molten　pool.　For　the　GH3128　high-temperature　alloy　thin　plate,　the　method　could　adjust　the　longitudinal　residual　stress　of　the　weld　without　peening　during　welding　from　the　average　value　of　390.9　MPa　to　116.1　MPa,　showing　a　70%　reduction.　Moreover,　this　method　could　reduce　the　warpage　deformation　of　the　component　perpendicular　to　the　weld　direction　by　74.5%　and　the　dimensional　shrinkage　along　the　weld　direction　by　80%.　Moreover,　for　the　multi-pass　welding　of　cylindrical　thin-walled　06Cr19Ni10,　the　dimensional　shrinkage　was　reduced　from　0.95　mm　(without　peening)　to　0.29　mm　(with　peening　during　welding).　©　2020,　Chinese　Lasers　Press.　All　right　reserved.