Taking　cracked　cantilever　beam　system　as　the　research　project,　a　finite　element　model　of　straight-cracked　cantilever　beam　was　established　on　the　basis　of　the　ANSYS　by　using　beam,　plane　and　contact　elements.　The　contact　elements　were　used　to　simulate　breathing　effects　of　crack,　and　the　effectiveness　of　the　as-proposed　model　was　verified　by　comparing　with　the　natural　frequency　in　the　literature.　Under　impulsive　and　sinusoidal　excitation,　the　effects　of　friction　on　vibration　characteristics　were　analyzed　based　on　the　model.　The　change　rules　of　system　damping　ratio　and　natural　frequency　with　the　crack　depth　and　crack　position　were　analyzed　with　ignoring　friction.　The　results　showed　that　the　interface　friction　of　crack　has　few　effects　on　system　vibration,　and　damping　ratio　could　be　used　as　a　parameter　of　crack　detection　to　some　extent.　©　2017,　Editorial　Department　of　Journal　of　Northeastern　University.　All　right　reserved.