A　novel　coordination　polymer　{[Cu(en)2][Ag2I　4]}n　(en　=　ethylenediamine)　was　synthesized　by　the　reaction　of　NaAgI2　and　Cu(en)2(NO3)　2·2H2O　at　room　temperature　with　pH　=　6.0,　and　the　structure　was　characterized　by　X-ray　single-crystal　diffraction.　It　crystallizes　in　monoclinic,　space　group　C2/m,　with　a=10.646(2),　b　=　13.304(3),　c　=　6.8445(14)　Å,　β　=　118.95(3)°,　C4H16N　4CuAg2I4,　Mr　=　907.10,　V　=　848.3(4)　Å3,　Z　=　2,　Dc　=　3.551　g/cm3,　F(000)　=　806,　μ(MoKα)　=　10.787　mm-1,　the　final　R1　=　0.0256　and　wR2　=　0.0654　for　900　observed　reflections　with　I　>　2σ(I).　According　to　structural　analysis,　the　title　compound　consists　of　template　cation　[Cu(en)2]2+　and　inorganic　chain　[Ag　2I4]n2-.　The　polymeric　negative　chain　[Ag2I4]n2-　is　built　up　from　pairs　of　AgI4　tetrahedron　by　sharing　one　edge.　Through　N-H⋯I　hydrogen-bonding　interactions,　the　whole　structure　represents　a　quasi-two　dimensional　arrangement.　Electrostatic　attraction　exists　between　organic　cations　and　inorganic　chains,　leading　to　a　so-called　organic-inorganic　hybrid　structure.