The mol-ecule of the title compound, C(23)H(18)Cl(2)N(4)O, assumes a non-planar conformation in which the pyrazolone ring forms dihedral angles of 32.61 (19), 76.73 (14) and 52.57 (19)° with the three benzene rings. The secondary amino group is involved in an intra-molecular N-H⋯O hydrogen bond. In the crystal, mol-ecules are linked by pairs of N-H⋯O hydrogen bonds, forming inversion dimers. An offset stacking inter-action is observed between the chloro-substituted benzene rings protruding on both sides of these dimers [centroid-centroid distance = 3.862 (1) Å].