The apparent molar volume (V-(empty set)) and isentropic compression (IC(empty (set),s)) of glycine, L-alanine and L-valine have been studied in (0.025, 0.05, 0.075 and 0.1) mol.kg(-1) aqueous 1-butyl-4-methyl pyridinium chloride ([C(4)mpy]Cl) solutions over a range of temperatures (288.15, 293.15, 298.15, 303.15 and 308.15) K from the values of densities (p) and ultrasonic speed (c), repectively. The standard partial molar volumes (V-(empty set)(0)), standard partial molar isentropic compression (K-(empty set),s(0)), and experimental slopes (S-v and S-K) have been determined for these amino acid solutions from the Masson equation and have been interpreted in terms of solute-solvent and solute-solute interactions, respectively. The hydrophilic-hydrophilic, hydrophilic hydrophobic and hydrophobic-hydrophobic interactions are involved in the studied systems of [C(4)mpy]Cl + amino acids + H2O by calculating the corresponding transfer functions (Delta V((empty set))(0)and Delta K-(empty set),s(0)). The contribution of the charged end groups (NH3+, COO-), (-CH2) group and other alkyl chains of the amino acids were estimated using V-(empty set)(0) values. Hydration number (n(H)) for studied amino acids in aqueous [C(4)mpy]Cl solutions are positive, which suggest a strong dehydration effect of [C(4)mpy]Cl. The obtained parameters will be helpful to understand mixing effects and other complex biological processes between head and side chain group of amino acids and ionic liquid [C(4)mpy]Cl in aqueous solution. (C) 2017 Elsevier Ltd.