A 6(5)8 CdSO4-type 3-D framework built by hexa-Cu" sandwiched polyoxotungstates [Cu(en)2]2-[Cu(deta)(H2O)]2[Cu6(en)2(H2O)2(B-alpha-GeW9O34)2] x 6H2O (1) (en = ethylenediamine and deta = diethylenetriamine) has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrometry, thermogravimetric analysis and single-crystal X-ray diffraction. To the best of our knowledge, 1 represents the first 3-D TMSP with 6(5)-8 CdSO4 topology in polyoxometalate chemistry. Magnetic measurements performed on 1 indicate the occurrence of ferromagnetic interactions within the copper ions and the coupling constants can be determined.