Recently, the design and synthesis of microporous metal-organic frameworks (MOFs)have attracted considerable attention in materials chemistry due to the formation of fascinating topologies and potential applications1-4.A novel three-dimensional(3D) microporous lanthanide-organic framework [Eu2(e,e-chdc)2(a,a-chdc)(H2O)4]n·6nH2O (1)(H2chdc=1,4-cyclohexanedicarboxylic) has been prepared under hydrothermal conditions and characterized single crystal X-ray diffraction.The results of an X-ray crystallographic analysis revealed that 1 has a 3D nanotubular structure.And the least stable a,a-conformation of the ligand is encountered in 1.It crystallizes in the triclinic stytem, space group P-1 with a =10.1184(7)(A), b=10.4118(7)(A), c =10.7273(7)(A), α =111.6960(10)°, β =117.5700(10)°, γ =92.2070(10)°, V=900.18(10) (A)3, Z =1, S=1.040, R1 =0.0254, wR =0.0701.