In the title complex, [Cu(C(2)H(8)N(2))(2)(H(2)O)(2)](C(13)H(9)O(2))(2)·2.66H(2)O, the Cu(II) centre (located at an inversion centre) is coordinated by two bidentate ethyl-enediamine (en) ligands and two water O atoms in a typical Jahn-Teller distorted octahedral geometry. The amino groups and the water mol-ecules are disordered over two distinct crystallographic positions with occupancies of 1/3 and 2/3. In the crystal, the cations and anions are disposed in alternating layers. One of the water mol-ecules of crystallization is disordered and the other has a fractional occupation. In the 2/3 occupancy component, water mol-ecules are organized into a chain composed of hexa-meric units inter-connected by carboxyl-ate bridges.