A novel Cu–azido complex modified hexa-CuII substituted sandwich-type phosphotungstate [Cu(en)2]{[Cu2(en)2(μ-1,1-N3)2(H2O)]2[Cu6(en)2(H2O)2(B-α-PW9O34)2]}·6H2O (1) (en=ethylene-diamine) has been prepared under hydrothermal conditions and structurally characterized by elemental analyses, IR spectra, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction. 1 displays a beautiful 1-D chain architecture constructed from sandwich-type [Cu2(en)2(μ-1,1-N3)2(H2O)]2[Cu6(en)2(H2O)2(B-α-PW9O34)2]2− units and [Cu(en)2]2+ linkers. To our knowledge, 1 represents the first hexa-CuII sandwiched phosphotungstate with supporting Cu–azido complexes.