The excellent properties of organic-inorganic nanocomposites garnered extensive attention in energy storage applications. In this regard, polyaniline-nickel oxide (PANI-NiO) has been synthesised using a chemical oxidation technique for supercapacitor applications. The structural, optical, and morphological properties of the PANI and PANI-NiO electrode materials were elaborated using X-ray diffraction (XRD), ultraviolet-visible (UV-Vis.), Fourier transform infrared (FTIR) spectroscopy, and field effect transmission (FESEM) techniques respectively. The electrochemical properties of the developed materials were explored via cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS) techniques. The PANI and PANI-NiO exhibited the specific capacitance values of 223.92 and 522.45 F/g respectively, at a current density of 1 A/g. The stability study of the electrodes shows a high capacitance retention of 79.5% after 3000 GCD cycles for the PANI-NiO electrode and 62.2% for the PANI electrode. Thus, the obtained results of the electrochemical test confirmed the exciting potential of the PANI-NiO compared to PANI in supercapacitor applications.