A new compound, {[Sm2L3(H2O)(4)]center dot(4,4'-bpy)center dot 3H(2)O(1)}(n) (1, H2L = 5-(3-pyridyl methoxy) isophthalic acid, 4,4'-bpy = 4,4'-dipyridyl), has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction. It crystallizes in triclinic, space group P (1) over bar with a = 11.266(2), b = 15.530(3), c = 16.711(3) angstrom, alpha = 112.803(3), beta = 90.526(1), gamma = 94.006(3)degrees, V = 2686.6(9) angstrom(3), Z = 2, D-c = 1.727 g/cm(3), mu = 2.251 mm(-1), F(000) = 1392, S = 0.999, the fmal R = 0.0296 and wR = 0.1058. In the title compound, two crystallographically independent Sm3+ cations are bridged by the carboxyl group of L2- ligands to form two different {Sm-2} binuclear subunits which are further connected by two distinct L2- ligands to shape a 1D chain, and such 1D chains are linked up to generate a 2D coordination polymer by another crystallographioally unique L2- ligand. The thermogravimetric analysis and luminescent property of the title compound were also investigated.