In this study, physical properties such as density, refractive index, surface tension and viscosity of aqueous potassium salt of L-phenylalanine (K-Phe) were measured over a temperature range of 298.15�343.15 K for various mass fractions (0.05�0.25) at atmospheric pressure. The effect of temperature and concentration of aqueous amino acid salt on corresponding physical property was studied. The experimental data were correlated using applied empirical correlations as a function of temperature and concentration. Statistical analysis was performed in order to evaluate the performance of applied empirical correlations. The correlated data of physical properties were in good agreement with the experimental data. Moreover, the density data were used for the estimation of coefficient of thermal expansion, while viscosity data were used for the calculation of activation energy. Furthermore, ANOVA analysis was carried out in all the cases to determine the significant influence of temperature and concentration on physical properties. © 2016 Institution of Chemical Engineers