A rubidium organic-inorganic hybrid complex, {H2[Rb(PMo12O40)(CH3CN)3](dpdo)2(H2O)2} n (1), (where dpdo is 4,4′-bipyridine-N,N′-dioxide) with special channels for the chainlike assembly of decorated Keggin-type anions was synthesized and structurally characterized. The crystal structure was determined by single-crystal X-ray diffraction. The crystal is Orthorhombic space group Cmcm with a = 20.4713(18) A, b = 17.0529(15) A, c = 16.1968(14) A, V = 5654.2(9) A3, Z = 4, C26H31N7O46RbMo12P, M = 2445.30, D c = 2.873 Mg m−3, μ = 3.570 mm−1, F(000) = 4640, the final R = 0.0438 and wR = 0.1350 for 2065 observed reflections with I > 2σ(I). Compound 1 exhibits a 3D network with large channels hosting decorated polyanion chains as guests.