In this work, we studied intermolecular aqueous clusters of biuret, an important urea derivative. FTIR showed an increase in the intensity of absorption bands when water molecules are introduced into the biuret. X-ray diffraction analysis showed that the introduction of water molecules into the biuret structure significantly increases the intensity of the bands on the diffraction patterns in the range from 14 to 65 2˚⊖. Aqueous biuret clusters have also been studied in the gas phase by theoretical methods: density functional theory and Atoms in Molecules (AIM) using the DFT level B3LYP/6–31 + G (d, p). The nature of molecular interactions between water and biuret through hydrogen bonds was also investigated using the electron localization function (ELF) and non-covalent reduced density gradient (NC-RDG). The thermodynamic and Non-linear optical properties of biuret-water clusters were performed also.