The density, viscosity, and heat capacity of aqueous potassium serinate solutions were measured over the temperature range from (298.15 to 353.15) K in the mass fraction range of (7.2 to 57.3) %. Each physical property was correlated with temperature and mass fraction, by regression analysis, and the corresponding coefficients for each property are presented here. The surface tension of the aqueous potassium serinate solution was also measured over the mass fraction range of (7.2 to 57.3) % at 298.15 K. In addition, the solubility of carbon dioxide in a 14.3 mass % aqueous potassium serinate solution was measured at (313.15, 343.15, and 373.15) K over partial pressures of CO2 ranging from (0.1 to 400) kPa. It was shown that the aqueous potassium serinate solution could be a good CO2 absorbent because of its high cyclic CO2 absorption capacity. Furthermore, it might be suitable for membrane gas absorption due to its higher surface tension.