The　hydrothermal　reaction　of　V2O5,　Cu(CH3COO)2　·　H2O,　TMAOH　and　1,2-diaminopropane　gave　a　novel　three-dimensional　framework　material,　{[Cu(1,2-pn)2]4[V18O42(H　2O)]}n　·　8nH2O,　which　was　constructed　from　the　mixed-valence　{V18O42(H2O)}　clusters　interconnected　through　{Cu(1,2-pn)2}　complex　groups.　{[Cu(1,2-pn)2]4[V18O42(H　2O)]}n　·　8nH2O　was　characterized　by　IR,　TGA　and　single-crystal　X-ray　diffraction.　It　crystallizes　in　tetragonal　space　group　P4/nnc　with　a=1.510　7(2)　nm,　c=　1.864　5(4)　nm,　Dc=2.028　g/cm3,　Z=2,　R1=0.063　1,　wR2=0.153　8.