In　order　to　depict　the　propagation　characteristics　of　Lamb　waves　in　beams,　and　quantitatively　detect　the　lamination　defect,　an　aluminium　beam　structure　is　used　as　a　research　object　by　using　both　finite　element　and　experimental　analysis,　respectively.　Based　on　the　combination　of　Matlab　and　ABAQUS,　a　three-dimensional　finite　element　model　of　aluminum　beam　with　lamination　defect　is　constructed.　By　extracting　the　time　domain　signal　of　the　rectangular　receiving　area　covering　the　defect,　the　behaviours　of　Lamb　wave　interacts　with　lamination　defect　are　studied.　Two　circumstance,　symmetric　boundary　and　free　boundary,　are　simulated　to　discuss　the　consistency　and　difference　of　the　amplitude　distribution　in　the　wavefield.　The　phenomena　of　the　incident　wave　amplitude　varies　with　the　beam　width　is　obtained.　Meanwhile,　the　EMAT/laser　detection　system　is　set　up　to　verify　the　finite　element　simulation　results,　and　found　that　the　two　have　good　consistency.　For　the　complex　time　domain　information　in　the　received　waveforms,　the　space-frequency-wavenumber　method　is　used　to　locate　and　quantitatively　evaluate　the　lamination　defect　in　the　aluminum　beam.　The　results　of　the　study　indicate　that　the　measurement　error　is　about　6%　in　both　simulation　and　experimental　analysis　by　using　space-frequency-wavenumber　method.　©　2019　Journal　of　Mechanical　Engineering.