In the mononuclear copper(II) title complex, [Cu(C11H16N3O)(H2O)]Br, the Cu(II) atom is coordinated by one O and three N atoms of the Schiff base ligand that forms together with one water mol-ecule a slightly distorted [CuN3O2] square-pyramidal polyhedron. The deviation of the Cu(II) atom from the mean equatorial plane is 0.182 (2) Å. The equatorial plane is nearly coplanar to the aromatic ring of the ligand [angle between planes = 10.4 (1)°], and the water molecule is situated in the apical site. All coordinating atoms (except the imine nitro-gen) and the bromide ion contribute to the formation of the N-H⋯Br, O-H⋯Br and O-H⋯O hydrogen bonds, which link mol-ecules into chains along [01-1].