The title anti-pyrine derivative, C(22)H(19)N(3)O(2), was synthesized by the reaction of 4-amino-1,5-dimethyl-2-phenyl-1,2-dihydro-pyrazol-3-one and 1-hy-droxy-naphthalene-2-carbaldehyde in methanol solution. As expected, the compound adopts a trans configuration about the central C=N bond. The N atom is involved in an intra-molecular O-H⋯N bond which stabilizes the mol-ecular configuration. In the crystal structure, adjacent mol-ecules stack with no short contacts.