The　generation　of　defects　has　a　great　influence　on　the　vibration　characteristic　of　roller　bearings.　Thus,　it　is　very　important　to　analyze　the　vibration　mechanism　of　bearings　with　different　kinds　of　defects　by　dynamic　models　which　can　make　systematic　descriptions　of　truly　dynamic　behavior.　In　this　paper,　dynamic　models　are　developed　based　on　the　model　proposed　by　Gupta　to　investigate　the　vibration　mechanism　of　cylindrical　roller　bearings　with　localized　defects.　The　inner　raceway　and　rollers　have　five　degrees　of　freedom　(DOFs)　in　the　model　to　better　describe　the　complex　dynamic　behavior　of　bearings.　Gyroscopic　moment,　centrifugal　force　and　lubrication　traction/slip　between　roller/raceway,　roller/cage,　cage/raceway　are　completely　included.　Moreover,　modeling　methods　of　single　defect,　multi-defects　and　compound　faults　are　introduced　with　the　consideration　of　additional　deflection　and　the　change　of　contact　force　direction　caused　by　defects.　The　differential　equations　used　to　describe　the　motions　of　bearing　components　are　solved　by　the　fourth　order　Runge-Kutta-Fehlberg　scheme　with　step-changing　criterion.　Vibration　responses　of　bearings　with　single　defect,　multi-defects　and　compound　faults　are　simulated　by　the　models　and　analyzed　in　both　time　domain　and　frequency　domain.　Experiments　have　been　carried　out　on　bearing　test　rig.　The　validity　of　models　built　in　the　paper　is　proved　by　comparing　the　simulation　results　with　experiments.　In　addition,　fruitful　vibration　responses　are　discovered　and　proposed,　which　will　provide　strong　theoretical　supports　for　fault　diagnosis　of　cylindrical　roller　bearings.　©　2020