A　new　inorganic/organic　hybrid　REV)(Cu2I4.　2I(2))]n　consisting　of　inorganic　copper　iodide　(Cu2I4　212)2n-　layer　and　organic　ethyl　viologen　(EV2+)　has　been　synthesized　and　structurally　described.　In　inorganic　moiety,　the　existence　of　weak　I　.　.　.　1　bonds　extend　(Cu214)2nn-　chains　into　2-D　layer　via　the　bridged　12　molecules.　The　device　based　on　[(EV)(Cu2I4　.2I(2))]　sandwiched　between　Ag　and　Si/Si02　electrodes　exhibits　reversible　electrical　bistability　behavior　with　ON/OFF　ratio　of　10(3).　And　its　electrical　bistability　mechanism　can　be　explained　as　the　conformational　change　with　respect　to　I-2　association　and　dissociation　from　copper　iodide　judging　from　DFT　calculations.