In　this　paper,　a　cylindrical　aluminum　sample　with　an　eccentric　circular　hole　was　prepared,　and　ultrasonic　measurements　were　carried　out　by　experimental　means.　The　measurement　area　was　limited　to　a　plane　edge　perpendicular　to　the　axis　of　the　cylindrical　component.　The　measured　waveform　data　were　input　into　the　formula　of　approximate　correction　method,　and　the　section　image　was　obtained　by　using　a　modified　Born　approximation　(MBA)　method.　Then,　the　three-dimensional　(3D)　shape　of　the　defects　in　the　aluminum　sample　was　reconstructed　by　superimposing　the　cross-sectional　images.　Results　showed　that　the　defect　reconstruction　effect　of　the　two-dimensional　section　and　the　3D　defect　reconstruction　effect　were　significantly　improved　by　the　MBA　method.　©　2022　Gangfeng　Zheng　et　al.