Lamb　wave　has　become　an　important　non-destructive　measurement　method　due　to　its　advantages　of　small　attenuation,　easy　excitation,　and　simultaneous　inversion　of　multiple　parameters.　According　to　its　propagation　properties,　we　proposed　an　improved　particle　swarm　optimization　method　for　the　inversion　of　the　thickness　and　elastic　constants　of　plates　in　the　study.　Numerical　simulations　and　validation　experiments　further　confirmed　that　the　Young＇s　modulus,　Poisson＇s　ratio,　and　thickness　of　plates　could　be　accurately　obtained　from　the　measured　zero-order　modal　Lamb　wave　dispersion　curves.　Then,　through　a　series　of　orthogonal　experiments,　the　influences　of　the　error　sources　of　measurement　points　on　inversion　parameters　were　explored.　In　addition,　the　statistical　significance　of　the　above　influences　on　each　inversion　parameter　is　discussed　in　detail.　This　study　provides　a　basis　for　the　accurate　and　efficient　non-destructive　measurements　based　on　Lamb　waves.