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The analysis of fluorescence 2D and 3D spectra of tryptophan (Trp), tyrosine (Tyr) and phenylalanine (Phe) measured in physiological solution at 293 K are presented. The spectral characteristics of 2D fluorescence spectra of amino acids (AAc) are recorded in the following conditions: for Trp λex/λem=280/357, for Tyr 275/303 and for Phe 257/283 nm, and the 3D spectra of AAc recorded in λex=200–450 and λem=200–500 nm ranges are given. It has been revealed that 3D spectra of AAc are characterized by two strong excitation/emission peaks located at λex/λem=230/350 and 280/350 nm. The high energy emission (absorption) at 230 nm is due to n→π* or π→π* transitions of the carboxylic or amide group and low energy emission (absorption) at 280 nm is due to π→π* transition in the indole ring. In 3D spectra Rayleigh scattering peak and second-order scattering peak are identified as well.