The partial molar volumes of glycine, DL-alanine, DL-serine, DL-threonine, L-histidine and glycylgIycine were obtained in water and aqueous solutions of 0.15 mol . dm(-3) dimethyl sulfoxide, 2.0 mol . dm(-3) sodium chloride and 0.15 mol . dm(-3) dimethyl sulfoxide/2.0 mol . dm(-3) sodium chloride at T = (278.15, 288.15, 298.15, and 308.15) K from the measurements of density. The data show that a low molarity of DMSO (0.15 mol . dm(-3)) exerts st slight influence on the partial molar volume of amino acids and peptides. However a 2.0 mol . dm(-3) sodium chloride aqueous solution changes the partial molar volumes of amino acids and peptides considerably. The transfer volumes of amino acids and peptides from water to aqueous solutions of sodium chloride are positive and may be regarded as a result of a dominant interaction between sodium chloride ions and the charged centres of amino acids and peptides. Their partial molar volume variations with temperature are discussed.