This　paper　provides　some　simulated　surface　cracks　whose　shape,　size　and　extension　mode　are　very　close　to　the　real　cracks　to　study　the　validity　of　the　method　of　using　surface　waves　to　evaluate　the　crack　depth.　The　reflection　and　transmission　coefficients　of　Rayleigh　waves　at　cracks　with　different　depths　were　obtained　by　using　finite　element　method　(FEM).　Experiments　were　performed　at　a　specimen　with　8　simulated　surface　cracks　and　three　couples　of　EMAT　were　employed.　It　shows　that　the　measured　transmission　coefficients　are　virtually　consistent　with　the　FEM　results,　while　the　measured　reflection　coefficients　are　obviously　smaller　than　the　FEM　results,　and　the　difference　is　positively　correlated　with　the　frequency　of　Rayleigh　waves.　As　a　consequence,　the　depths　of　the　simulated　cracks　were　evaluated　by　comparing　the　measured　transmission　coefficients　with　the　FEM　obtained　reference　curves.　At　last,　a　crack　depth　quantitative　detection　method　based　on　arrival　time　difference　between　low-frequency　transmitted　wave　and　delay　transmitted　wave　is　proposed.　©　2020　IEEE.