A　variable　cross-section　cantilever　beam　structure　for　the　piezoelectric　energy　harvester　is　proposed　in　this　paper.　The　finite　element　simulation　analysis　of　the　vibration　characteristics　and　output　voltage　shows　that　the　proposed　structure　is　beneficial　to　improve　the　power　generation　performance.　The　fixed　end　of　the　energy　harvester　is　a　uniform　cross-section　beam　and　the　free-end　is　a　variable　cross-section　beam.　The　piezoelectric　layer　is　adhered　on　the　surface　of　the　uniform　cross-section　beam.　A　variety　of　different　forms　of　variable　cross-section　cantilever　beam　can　be　obtained　by　changing　the　width　ratio　of　the　free-end　to　the　fixed　end　of　the　cantilever　beam.　The　natural　frequencies,　stress　and　strain　distributions　as　well　as　the　output　voltage　response　of　harmonic　excitation　of　the　triangular　beam,　rectangular　beam　and　the　trapezoidal　beam　with　different　widths　ratio　are　compared　and　analyzed.　The　results　show　the　triangular　beam　exists　higher　natural　frequency　and　maximum　output　voltage.　The　effects　of　different　variable　cross-section　range　lengths　on　the　output　voltage　are　analyzed.　The　output　voltage　of　different　width　ratio　energy　harvester　with　the　same　first　order　frequency　is　analyzed,　which　shows　that　the　output　voltage　of　the　unit　volume　piezoelectric　layer　of　triangle　structure　is　the　largest.　The　output　voltage　characteristics　of　the　root-bonded　piezoelectric　patches　and　the　all-bonded　piezoelectric　patches　on　the　base　layer　were　compared　and　analyzed.　The　results　show　that　the　former　has　a　larger　output　voltage　and　better　power　generation　performance.　©　2018,　Editorial　Department　of　Journal　of　Piezoelectric　and　Acoustooptic.　All　right　reserved.