To　solve　the　problem　of　processing　quality　degradation　due　to　vibration　in　the　robot　bonnet　polishing　system　(RBPS),　the　vibration　generation　mechanism　of　the　polishing　system　is　revealed　based　on　the　modal　analysis　and　dynamic　modeling　of　the　RBPS.　The　modal　analysis　results　showed　that　the　operating　frequency　of　the　system　is　near　the　natural　frequency,　which　makes　the　system　susceptible　to　resonance.　On　the　other　hand,　the　forced　vibration　caused　by　the　polishing　force　leads　to　high　vibration　at　the　end　of　the　robot　during　the　polishing　process.　In　order　to　suppress　the　vibration　generated　by　the　polishing　system　and　optimize　the　dynamic　characteristics　of　the　polishing　system,　a　vibration　suppression　method　to　increase　the　damping　ratio　of　the　system　was　proposed.　The　experiments　of　SiC　fixed　point　polishing　were　performed　using　both　vibration　suppression　bonnet　and　original　bonnet.　The　surfaces　RMS　and　PV　of　the　parts　polished　by　the　vibration　suppression　bonnet　were　generally　better　than　those　of　the　original　bonnet.　The　vibration　suppression　bonnet　has　improved　the　convergence　ratio　of　RMS　and　PV　by　42.59%　and　19.56%　respectively　over　the　original　bonnet　in　the　whole　surface　polishing　experiments.　The　PSD　analysis　illustrated　that　the　vibration　suppression　bonnet　can　better　suppress　the　intermediate　frequency　errors.　The　effectiveness　of　the　method　in　suppressing　vibration　and　improving　machining　quality　is　demonstrated.