Three-layer　structured　hybrid　bistable　devices　(HBDs)　utilizing　graphene　sheets　sandwiched　between　polymer　layers　were　fabricated　by　laminating　two　glass　substrates　coated　with　patterned　electrodes　and　spacers.　The　hybrid　devices　using　polystyrene　(PS)　and　poly　(vinyl-carbazole)　(PVK)　as　matrix　layer　for　graphene　sheets　demonstrated　write-once-read-many-time　and　volatile　memory　effects,　respectively.　It　is　found　that　the　memory　properties　of　the　HBDs　can　be　tailored　by　varying　the　depth　of　the　charge　traps　formed　between　the　polymer　matrix　and　graphene　sheets.　The　possible　operating　mechanisms　of　the　HBDs　were　analyzed　based　on　the　investigation　of　current-voltage　characteristics　for　the　hybrid　devices.　(C)　2011　Elsevier　B.V.　All　rights　reserved.