Ag/PEDOT:PSS:PVP/Ta　memristor　were　fabricated　by　spin-coating.　The　device　conductance　can　change　quasi-continuously.　The　essential　electrical　properties　of　the　memristor　including　short　term　plasticity　transform　long　term　plasticity　and　spike　rate　dependent　plasticity　were　observed.　The　test　results　show　that　the　range　of　conductance　variation　under　forward　voltage　bias　is　increased　and　the　relaxation　time　curve　of　memory　is　enhanced,　due　to　doping　PVP　into　the　organic　layer,　which　decreases　the　conductance　of　the　organic　layer.　The　device　has　very　large　change　range　of　conductance　that　can　be　recognized　easily　by　external　circuits.　And　the　device　shows　a　good　ability　of　consistency.　Therefore,　the　device　could　be　used　for　large-scale　neuromorphic　circuits.　©　2016,　Chinese　Ceramic　Society.　All　right　reserved.