In the title compound, C20H21NO4, the two benzene rings are almost perpendicular to each other, making a dihedral angle of 86.1 (7)°. The hydroxyethanimine group is essentially coplanar with the benzene ring, the largest deviation from the mean plane of the hydroxyethanimine [C=N—OH] group being 0.011 (1) Å for the O atom. An intramolecular C—HO hydrogen bond occurs. The molecules are linked into cyclic centrosymmetric R 2 2(6) dimers via O—HN hydrogen bonds. Intermolecular C—HO hydrogen bonds link the molecules, forming a C(8) chain along the a axis. The crystal packing is further stabilized by C—Hπ interactions.