In the title compound, [Cu(C(13)H(20)N(3)O(2))(NO(3))](n), the Cu(II) atom is chelated by the Schiff base ligand via three N atoms and one O atom lying in an approximate square plane (r.m.s. deviation = 0.04 Å). The complex mol-ecules are linked into a polymeric chain by bridging nitrate anions, forming axial Cu-O bonds of 2.535 (6) and 2.676 (7) Å, completing a distorted octa-hedral coordination geometry. The NH groups of the ligand form hydrogen bonds to the nitrate anions.