The title compound, C10H12N2O4, adopts a trans configuration with respect to the C=N double bond. The non-H atoms of the molecule are essentially coplanar, with a maximum deviation of 0.015 (2) Å. An intramolecular O—HN interaction is observed. In the crystal structure, the molecules are linked into a two-dimensional network parallel to the ac plane by N—HO hydrogen bonds involving the methoxy O atom and by two C—HO hydrogen bonds involving the carbonyl O atom. In addition, an intermolecular C—Hπ interaction is observed.