A binuclear complex [Eu-2(HOC6H4CH2COO)(6)(C10H8N2)(2)(H2O)(2)]center dot H2O (1) was synthesized and characterized by X-ray diffraction single-crystal structure analysis. The synthesis was based on the reaction of p-hydroxyphenyl acetic acid, 4,4'-bipyridine and Eu(NO3)(3)center dot 6H(2)O in mixed solution of water and ethanol. The complex C68H64N4O21Eu2, crystallizes in triclinic, space group Pn with a = 1.17504(2) nm, b = 1.62913(3) nm, c = 1.84424(4) nm, alpha = 83.599(1 degrees), beta= 72.054(1)degrees, gamma = 71.038(1)degrees, V = 3.17614(11) nm(3), Mr = 1577.15, mu(MoK alpha) = 2.039 mm(-1), Dc = 1.649 g/cm(3), F(000) = 1588, Z = 2, the final R = 0.0255, omega R = 0.0599 for 11865 observed reflections [I>2 sigma(I)]. Each Eu(III) atom is in a distorted monomap square-antiprismatic environment, surrounded by eight oxygen atoms from carboxyl and water molecules, one nitrogen atom from 4,4'-bipyridine. The occurance of numerous O-H center dot center dot center dot O involving coordinated and non-coordinated water molecules build up an intricated three dimensionnal network.