In the title Schiff base salt, C16H13N2O(+)·ClO4 (-), the pyridine ring and the naphthalene ring system are approximately co-planar [making a dihedral angle of 6.05 (12)°] and an intra-molecular O-H⋯N hydrogen bond occurs between the hydroxyl and imino groups. In the crystal, the cations and anions are linked by N-H⋯O and weak C-H⋯O hydrogen bonds, forming the supra-molecular layers parallel to (100). The crystal studied was an inversion twin refined with minor component = 0.43 (13).