Novel semi-organic single crystals of bis (potassium) 2,4-dinitrophenolate monohydrate were grown by slow evaporation technique at room temperature. Sin- gle-crystal XRD confirms that the crystal belongs to monoclinic system with space group C2/c. 1 H NMR and 13 C NMR studies were conducted for the crystal. In order to know the purity, LC-MS studies were also conducted for the crystal. Functional groups present in the synthesized compound were confirmed by FT-IR analysis. UV-Vis studies show that the crystal has a lower cutoff wave length at 461 nm. Dielectric studies were carried out to study the charge transport mechanism in the crystal. Photoconduc- tivity study exhibits the positive photoconductivity nature of the grown crystal. Nonlinear absorption coefficient (b), nonlinear refraction (n2), and third-order susceptibility (v (3) ) were also evaluated for the grown crystal.