In the title Schiff base, C13H9Cl2NO2, which arose from the condensation of 3,4-dichloroaniline with 2,3-dihydroxybenzaldehyde, the dihedral angle between the aromatic rings is 44.74 (13)°. Intramolecular O—H⋯O and O—H⋯N hydrogen bonds close S(5) and S(6) rings, respectively. In the crystal, inversion dimers linked by pairs of O—H⋯O hydrogen bonds generate R
2
2(10) loops. A weak C—H⋯π interaction is also observed.