The　dielectric　elastomer　(DE)　is　an　insulating　membrane　with　extra-ordinary　properties　which　can　meet　various　electromechanical　failures　during　the　actuation.　In　the　current　work,　we　measured　breakdown　voltage　in　DE　membrane　with　special　focus　on　the　varying　boundary　stress　during　the　actuation　process.　The　boundary　stress　tuned　deformation　state,　causing　the　membrane　to　deform　out-of-plane　before　breakdown.　A　theoretical　model　is　presented,　involving　the　strain-stiffening　effect　in　material　and　boundary　stress　effect　in　geometry,　to　estimate　the　dielectric　breakdown　voltage.　The　results　agree　with　the　experiments.　Then,　another　set　of　experimental　investigation　is　conducted　to　study　the　voltage　induced　wrinkling　of　DE　membrane.　Steady　wrinkles,　without　an　accompany　of　electrical　breakdown　are　attained　and　three　different　failure　modes　of　DE　membrane　are　classified　into　a　phase　chart.　Finally,　a　qualitative　theoretical　explanation　on　wrinkling　mechanism　of　DE　membrane　is　presented　and　verified　by　experimental　observations.