© 2015, Elsevier B.V. All rights reserved.(Chemical Equation Presented). A polymeric potassium complex of p-nitrophenol was synthesized and characterized by analytical and spectroscopic techniques. Molecular structure of the complex was determined by single crystal X-ray diffraction study. X-ray structural data show that crystals contain polymeric K+ complex of p-nitrophenol. Asymmetric unit consists of one p-nitrophenolate, one K+ ion and one water molecule. All bond lengths and angles in the phenyl rings have normal Csp2-Csp2 values and are in the expected ranges. The p-nitrophenolate is close to planar with small distortions by some atoms. Each potassium ion in the polymeric structure is identical and eight-coordinate, bonded to four nitro, two phenolate oxygen atoms from five pnitrophenolate ligands and two oxygen atoms from two water molecules. Electronic, electrochemical, photoluminescence and thermal properties of the complex were also investigated.