Peptides are most important molecules due to their wide application in drug production and their role as signal transmitters in the cell communications. Therefore, the systematic study of peptides can prove valuable information about their behavior in solutions and insight into the conformational stability of proteins. Ultrasonic velocity and density values for ternary system (amino acid / di-peptide + salt + water ) i.e. glycylglycine each in 1.5 M aqueous solution of NaCl used as a solvent for variable concentrations of glycylgycine in the range of 0.00 to 0.15 molality at a temperature 303.15K. Using ultrasonic velocity and density data, the thermodynamic parameters such as molar volume (V),volume expansivity (α), specific heat (Cp), molecular radius (r0), Molwyn-Hughes parameter (C1), cohesive energy density (ε), internal pressure (Pi), change in entropy(Φ), disorder parameter (δ), interaction energy (E) and solubility parameter (δS). The observed intermolecular interaction shows ion–solvent, ion-ion and dipole-dipole interactions. The interaction of di-peptide like glycylglycine with aqueous electrolyte solutions due to its vital role in various biological processes in our life. The present study gives us valuable information about various parameters to explore the application of Glycylglycine in medicinal purpose.