The absorption and emission solvatochromism of five indole derivatives was studied by referring the shifts to the corresponding vapor-phase wave numbers. The emission results clearly demonstrate, in three cases, the change in the nature of the emitting state when the solvent polarity is increased. In absorption, a large red shift in the 1La band is observed in all polar solvents, and this cannot be explained by classical solvent–solute interaction forces. The temperature dependence of the emission shift in a viscous solvent (glycerol) confirms that most of the emission shift is due to solvent relaxation. The 1La–1Lb level inversion model applied to ground-state polar solvent–solute complex, can account for most of the solvatochromism features observed.