A novel organic–inorganic hybrid hexa-Ni II sandwiched germanotungstate [enH 2 ] 2 [Ni(en) 2 ] 2 {[Ni 6 (en) 2 (H 2 O) 2 ] [B-α-GeW 9 O 34 ] 2 }·14H 2 O (1) has been hydrothermally synthesized and structurally characterized. 1 consists of a hexa-nickel sandwiched polyoxoanion {[Ni 6 (en) 2 (H 2 O) 2 ][B-α-GeW 9 O 34 ] 2 } 8− , two discrete [Ni(en) 2 ] 2+ cations, two free diprotonated [enH 2 ] 2+ cations and fourteen lattice water molecules. Notably, the sandwich-type polyoxoanion {[Ni 6 (en) 2 (H 2 O) 2 ][B-α-GeW 9 O 34 ] 2 } 8− is constructed from two trivacant [B-α-GeW 9 O 34 ] 10− Keggin moieties in a staggered fashion linked via a belt hexa-nickel cluster [Ni 6 (en) 2 (H 2 O) 2 ] 12+ . To our knowledge, 1 represents the first hexa-Ni II substituted sandwich-type germanotungstate. 1 shows the occurrence of ferromagnetic interactions within nickel centers. The photocatalytic property of 1 has been investigated.