In the title compound, [Cu(C₄H₄O₄)(C₁₀H₈N₂)(H₂O)]·2H₂O, the Cu(II) ion displays a slightly distorted square-pyramidal coordination. The water mol-ecule at the apical position shows a long bond [Cu-O = 2.276 (2) Å]. The basal plane is formed by two N atoms of the 2,2'-bipyridine ligand and two carboxyl-ate O atoms from a malonate group. The five-membered chelate ring is almost planar [maximum deviation = -0.006 (2) Å], while the six-membered chelate ring defined by the malonate ligand adopts a distorted boat conformation. In the crystal, Cu(II) complex mol-ecules and lattice water mol-ecules are connected by O-H⋯O and C-H⋯O hydrogen bonds. The crystal packing is further stabilized by π-π inter-actions [centroid-centroid distances = 3.563 (2)-3.828 (2) Å].