Button　cutters　are　commonly　used　in　hard　rock　drilling　because　the　inserted　carbide　buttons　provide　exceptional　wear　resistance,　impact　resistance,　and　high　strength　in　challenging　geological　formations.　One　of　the　most　pressing　issues　in　designing　a　button　cutter　is　to　study　the　rock　breaking　mechanisms　of　carbide　buttons.　In　this　study,　the　three-dimensional　discrete　element　method　(DEM)　was　employed　to　investigate　the　rock　breaking　mechanism　and　cutting　performance　of　five　widely　used　carbide　buttons,　i.e.,　spherical,　saddle,　wedge,　conical,　and　parabolic　buttons.　The　simulation　results　were　compared　with　laboratory　tests　to　reveal　the　rock　indentation　process.　The　crack　propagation　pattern,　energy　dissipation,　and　damage　evolution　associated　with　the　force-penetration　depth　curve　were　investigated.　Tensile　damage　was　the　primary　determinant　for　crack　propagation　and　coalescence.　By　systematically　exploring　the　penetration　index,　specific　energy,　and　crack　propagation　characteristics,　the　conical　button　had　a　high　rock　breaking　efficiency　when　the　penetration　depth　was　low,　and　the　saddle　button　had　a　high　rock　breaking　efficiency　when　the　penetration　depth　was　high.　The　findings　can　provide　references　for　the　design　of　a　button　cutter.