Structural and non-linear optical (NLO) properties of a new anilinium hybrid crystal of chemical formula [(C6H7NCl + , NO3-)3] have been investigated. The crystal structure was determined from single crystal X-ray diffraction measurements performed at a temperature of 100K and shows that the compound crystalizes in a noncentrosymmetric space group (Pna2 1). The structural analysis was coupled to the Hirshfeld surfaces analysis to evaluate the contribution of the different intermolecular interactions to the formation of supramolecular assemblies in the solid state that obey nonlinear optical features. This analysis reveals that the studied compound is characterized by a three-dimensional network of hydrogen bonds and the main contributions are provided by the O…H, C…H, H... H and Cl...H interactions, which alone represent ~ 85% of the total contributions to the Hirshfeld surfaces. It is noteworthy that the Halogen…H contributions are quite comparable to those of H…H contacts. The nonlinear optical properties were investigated by nonlinear diffuse femtosecond-pulse reflectometry and the obtained results were compared to those of the reference material LiNbO3. The hybrid crystals exhibit notable second (SHG) and third (THG) harmonic generation that confirms its polarity generated by the different intermolecular interactions. These measurements also highlight that the THG signal of the new anilinium compound normalized to its SHG counterpart is more pronounced than for LiNbO3.