Molecular interactions of amino acids with ionic liquids are significant to study the molecular stability and physicochemical properties of amino acids. Mixtures of amino acids L-leucine and N-acetyl-L-leucine + (0.005, 0.010, 0.030, and 0.050 mol.kg(-1)) aqueous solution of ionic liquid (1-butyl-3-methylimidazolium chloride) at temperature T = (288.15, 298.15, 308.15, and 318.15 K) have been studied by density and speeds of sound measurements. Volumetric properties have been obtained by utilizing data of density. Volumetric properties include apparent molar volumes, partial molar volumes at infinite dilution, limiting partial molar volumes of transfer at infinite dilution, apparent molar expansibility, etc. Similarly, speeds of sound measurements are utilized to calculate corresponding parameters like apparent molar isentropic compression, K-phi s, apparent molar isentropic compression at infinite dilution, K-phi s(0) and transfer compressibility at infinite dilution Delta K(phi s)(. )(0)Results confirmed the predominance of the hydrophilic-hydrophilic interaction over the hydrophobic-hydrophobic interaction in ternary solutions.