Summary. The charge-transfer complexes (CT-complexes) between 2,3-dicyano-1,4-naphthoquinone ( DCNQ) and some aromatic anilines, both ring and N-substituted, were studied spectrophotometrically in three chlorinated solvents, viz. chloroform, dichloromethane, and 1,2-dichloroethane at different temperatures. All the donors are known to form stable 1:1 stoichiometric complexes with DCNQ and their stoichiometry was unaffected by the variation of temperature over the studied range. The change in polarity of the solvent also doesn’t affect the stoichiometry of the complexes. The determined formation constant values are in the range of 0.49–10.8 dm 3 mol −1, the highest is for the N-benzylaniline and the lowest is for o-chloroaniline. The effect of functional groups on the aniline moiety towards the strength and its electron releasing property has been discussed. The Δ H, Δ S, and Δ G values are all negative, so the studied complexes are reasonably stable and exothermic in nature. The ionization potentials of the donors were determined using the charge-transfer (CT) absorption bands of the complexes. The dissociation energies ( W) of the charge-transfer excited state for the CT-complexes were also determined and are found to be constant.