Inverse　photoconductance　is　an　uncommon　phenomenon　observed　in　selective　low-dimensional　materials,　in　which　the　electrical　conductivity　of　the　materials　decreases　under　light　illumination.　The　unique　material　property　holds　great　promise　for　biomedical　applications　in　photodetectors,　photoelectric　logic　gates,　and　low-power　nonvolatile　memory,　which　remains　a　daunting　challenge.　Especially,　tunable　photoconductivity　for　biocompatible　materials　is　highly　desired　for　interfacing　with　biological　systems　but　is　less　explored　in　organic　materials.　Here,　we　report　nanofibers　self-assembled　with　cyclo-tyrosine-tyrosine　(cyclo-YY)　having　voltage-regulated　inverse　photoconductance　and　photoconductance.　The　peptide　nanofibers　can　be　switched　back　and　forth　by　a　bias　voltage　for　imitating　biological　sensing　in　artificial　vision　and　memory　devices.　A　peptide　optoelectronic　resistive　random　access　memory　(PORRAM)　device　has　also　been　fabricated　using　the　nanofibers　that　can　be　electrically　switched　between　long-term　and　short-term　memory.　The　underlying　mechanism　of　the　reversible　photoconductance　is　discussed　in　this　paper.　Due　to　the　inherent　biocompatibility　of　peptide　materials,　the　reversible　photoconductive　nanofibers　may　have　broad　applications　in　sensing　and　storage　for　biotic　and　abiotic　interfaces.　©