Urea-adipic acid (UHA) co-crystal was synthesized and harvested at room temperature by the slow evaporation method. The single X-Ray diffraction of the crystal system and its lattice parameters of the UHA co-crystal were determined. The functional nature of the compound was analyzed using FT-IR and FT-Raman spectra. By the UV–Vis spectrum, the optical transmission property was estimated and the mechanical stability was found by Vickers microhardness experiment. Further, the thermal stability and melting point was studied by TG/DSC methods. In the range of frequencies 50 Hz -5 MHz at different temperatures 313 K, 333 K, 353 K, and 373 K the crystal dielectric behavior has been observed. Fluorescence study and lifetime-resolved decay computation were also performed. The SEM picture rendered the surface morphology of UHA crystal. The structural properties of the UHA crystal were computed utilizing the CAM-B3LYP method and 6–311++G(d,p) basis set and found agreeable with the experiment data (XRD). The linear polarizability (α) and hyperpolarizability (β) of first-order have also been determined. The HOMO and LUMO (bandgap) energies, molecular electrostatic potential and Non-linear optics (NLO) explain the chemical activity of the UHA confirming the advantage of the material. The UHA nonlinear optical characteristics of third-order have been analyzed by the Z-scan technique. © 2019 Elsevier B.V.