The molecular conformation of the title compound, C20H15Cl2N3O2, is stabilized by an intramolecular O—H...O hydrogen bond, forming an S(6) ring motif. The central pyridine ring is almost planar [maximum deviation = 0.074 (3) Å]. It subtends dihedral angles of 86.10 (15) and 87.17 (14)°, respectively, with the phenyl and dichlorophenyl rings, which are at an angle of 21.28 (15)° to each other. The =C(—OH)CH3 group is coplanar. In the crystal, molecules are linked by intermolecular N—H...N and C—H...N hydrogen bonds, and N—H...π and C—H...π interactions, forming a three-dimensional network. The most important contributions to the crystal packing are from H...H (33.1%), C...H/H...C (22.5%), Cl...H/H...Cl (14.1%), O...H/H...O (11.9%) and N...H/H...N (9.7%) interactions.