The present article report on synthesis and electrochemical supercapacitor application of bismuth oxide (Bi2O3) deposited on stainless still (SS) substrate using alow cost and simplest electrodeposition methods. The structural analyses of the produced samples reveal polycrystalline with a tetragonal crystal structure. It has been obtained to synthesized linked adherence and compact surface morphologyand TEM reveals nanoplates-like surface appearance. Electrochemical supercapacitive concert of Bi2O3 thin film electrode has been performed through cyclic voltammetry (CV), charge-discharge (CD), and impedance spectroscopy (EIS) in aqueous 1M KOH electrolyte. The Bi2O3 thin film electrode obtained the highest specific capacitance (SC) of 1227.5 F/g at 2 mV/Sec scan rate in 1M KOH. Obtained maximum value of specific energy (SE) and specific power (SP) was 191.14 Wh/Kg and 4.8 kW/kg at 18 mA/cm2 in 1M KOH electrolyte respectively. 93.29 % capacitance retention after 3500 CV cycles