In this present study, the structural, molecular, electronic, thermal studies, and the nonlinear optical (NLO) properties of a newly synthesized chalcone derivative 3-(2-chloro-phenyl)-1-[3-(2-oxo-2-phenyl-ethoxy)-phenyl]-propan-1-one (CPPO) were performed. The molecular structure of titled compound was described by single crystal X-ray diffraction, nuclear magnetic resonance spectroscopy (1H and 13C NMR) and thermal analysis (TGA-DTG analysis). The supramolecular arrangement in solid state was confirmed by Hirshfeld surface analysis and 2D-fingerprint plots. The CPPO compound was crystallized on non-centrosymmetric monoclinic space group P21 and the supermolecule approach (SM) at DFT/CAM-B3LYP/6-311++G(d,p) level was used to analyze the nonlinear optical properties in crystalline environment. The total moment of dipole, the averages of linear polarizability α(−ω;ω) and first and second hyperpolarizabilities, linear refractive index and the third-order nonlinear susceptibility (χ(3)) were calculated as function of the electric field frequency. The χ(3)-value of the CPPO crystal at 532 nm is 266 times greater than the experimental result of organic crystal (2E)-1-(3-bromophenyl)-3-[4(methylsulfanyl)phenyl]prop-2-en-1-one [1], demonstrating that CPPO crystal has good potential for use as NLO material.