A novel β-octamolybdate supported complex [Ba(DMF) 2 (H 2 O)] 2 [Mo 8 O 26 ]·2DMF (1) was synthesized by the direct modification to the surface of octamolybdate molecular cluster. Its structure was determined by elemental analysis, TG analysis, IR spectrum, and the single-crystal X-ray diffraction. The title compound crystallizes in triclinic system, space group P1̄, a=9.984(2)Å, b=11.117(2)Å, c=12.681(3)Å, α=115.86(3)°, β=97.66(3)°, γ=98.11(3)°, V=1223.5(4)Å 3 , Z=2, λ(MoKα)=0.71073Å, (R(F)=0.0386 for 5535 reflections). Data were collected on a Rigaku R-AXIS RAPID IP diffractometer at 293K in the range of 2.04<θ<27.47°. Compound 1 exhibits a novel two-dimensional (2D) layered framework in which all β-[Mo 8 O 26 ] 4− subunits are connected together through Ba–O–Ba–O–Mo and Ba–O–Mo bridges. Furthermore, these 2D layers are extended into 3D supramolecular network containing parallelogram channels via hydrogen-bonding interactions.