Enthalpies of solution of glycine, L-alanine, and L-serine in water and aqueous solutions of LiNO3, NaNO3, and KNO3 were measured at 298.15 K. Enthalpies of transfer (Delta(tr)H) of amino acids from water to aqueous solutions of nitrate salts were derived. The effect of the ion type, concentration, and structure of amino acids on the magnitude of the transfer enthalpies are discussed in terms of the electrostatic interaction and the structural hydration interaction model.