The title compound has been synthesised by the reaction of 2-hydroxy-1-naphthaldehyde with 2,5-dichloroaniline. The compound was characterized by elemental analysis, IR and UV-Visible techniques. The UV-Visible spectra of the Schiff base with OH group in ortho position to the imino group was studied in polar and nonpolar solvents in acidic and basic media. The structure of compound has been examined cyrstallographically. It crystallizes in the or-thorhombic space group P2(1)2(1)2(1) with a = 6.059(1), b = 12.105(2) c = 20.006(2) angstrom, V = 1467.4(3) angstrom(3), D-x = 1.431 g.cm(-3) and Z = 4. The crystal structure was solved by direct methods and refined by full-matrix least squares. Molecule of the title compound N-[2-hydroxy-1-naphthylidene]2,5-dichloroaniline is nearly planar. The molecule contains a strong intramolecular N...H-O hydrogen bond between the imine and hydroxyl group [O1 and N1 = 2.540(4) angstrom]. (c) 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.