The visible electronic spectra of the title hydroxyazo compound (abbreviated as HAI) in a number of organic solvents have been studied. It was found that in dilute solutions in basic solvents, HAI exists in an acid-base equilibrium of the type HAI H + + AI - . The proportional concentration of the conjugate base (AI - ) in the medium is largely dependent on the HAI concentration, the basicity of the organic solvent and the tendency of stabilization of the AI - form through H-bond interaction with the solvent molecules. The low energy visible band of both the HAI and AI - forms are assigned to a transition involving the whole solute molecule associated with intramolecular CT character. The effect of time on the longer wavelength visible band of HAI has been investigated.