Compound [V16O38(Cl)][Cu(enMe)(2)](3.5).2H(2)O(1) has been hydrothermally synthesized and characterized by means of single-crystal X-ray diffraction, elemental analysis, IR, EPR and TGA analysis. The X-ray crystallography shows that compound 1 contains a new {V16O38} cluster shell, which is connected by [Cu(enMe)(2)](2+) coordination fragments into a 3-D framework. The compound crystallized in a monoclinic system with space group P2 (1)/n, M=2235-82, a=1.26076 (3) nm, b = 2.55802 (6) nm, c = 2.14742 (4) nm, beta=90.7380(10)degrees, V=6.9250(3) nm(3), Z=4, F(000)=4418, D-c=2-145 g . cm(-3), mu=3.227 mm(-1), (Delta/sigma) = 0.000, S=1.066.