A new dissymmetrical oxamidate ligand has been used to construct a metal-organic network. Using this ligand, a novel coordination polymer, namely {[Cu(obea)]2Cu・CH3OH・H2O}n (1) [H3obea = N1-(2-carboxyphenyl)-N2-(2-hydroxyethyl)oxalamide] has been synthesized and characterized by single-crystal X-ray analysis. The structure of complex 1 consists of neutral trinuclear complex units. Through syn-anti carboxylate bridges, the complex features a 2D structure with a helical substructure. Its magnetic properties have been investigated.