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Raman data collected from free amino acid and peptide chains permit assignment of the seven markers located at approximately 1616, 1606, 1210, 1178, 850, 830, and 643 cm⁻¹ to tyrosine. The effects induced by labile hydrogen deuteration, temperature, concentration, and protonation–deprotonation on these Raman markers were analyzed. Following closely a recent multiconformational analysis on phenylalanine, we could confirm the predominance of gauche^‐/gauche^‐ rotamers with respect to the side chain χ₁/χ₂ torsion angles in both tyrosine and tyrosinate. Calculated Raman spectra, based on the consideration of both implicit and explicit hydration models, have revealed the effect of hydrogen bonding of water molecules to the phenol ring hydroxyl group of tyrosine. A special attention has been paid to the 850/830 cm⁻¹ tyrosine doublet, for which no intensity ratio inversion could be remarked when the …