Fluorescein is exclusively popular owing to bright fluorescence of its R2- dianion. While the structure of the latter and tautomerisrn of the H2R form are well established, only the species with COO- and OH groups has been supposed for HR- up to now. Using absorption, emission, and excitation at different pH in non-HBD solvents, DMSO, acetonitrile, and acetone, we reveal that 10-12% of HR- ions nevertheless exist as "phenolate" monoanion with nonionized COOH group.