Biocompatible chitosan-based polyelectrolyte complexes (PECs) doped with xanthene dyes (fluorescein, eosin Y, erythrosin В, rhodamine 6G) were synthesized and characterized by scanning electron microscopy, dynamic light scattering, zeta potential measurements, absorption and luminescence (including polarized, time-resolved and phosphorescence) spectroscopy. The results were discussed in terms of mechanism and rigidity of dye-PEC binding, heavy atom effect in dyes and PEC stability. Eosin Y was found to be an optimal dopant providing both a high dye content in PECs and a high quantum yield of fluorescence.