H2O2 is the product of reactions catalyzed by a large number of oxidases. It is essential in chemical, biological, food production, paper bleaching, sterilization clinical and many other applications. So, sensitive, rapid, and low-cost detection of H2O2 is of great practical importance in various fields such as medicine, food control and environmental analysis [1-4]. Electrochemical have been proved to be an inexpensive and effective way for hydrogen peroxide detection. The direct reduction or oxidation of H2O2 at bare electrode is not suited for analytical applications due to slow electrode kinetics and high overpotentials required for redox reactions of hydrogen peroxide. So, different redox mediators immobilized on the electrode surfaces have been used for decreasing of overvoltages and increasing of electron transfer kinetics. Manganese dioxide (MnO2) is an important functional oxide with distinctive properties and has wide applications in catalysis, molecular adsorption, biosensor and energy storage. Recently, MnO2 has appeared as one of the most promising electrode materials due to its low cost, high electrochemical activity, and environmentally friendly nature .In the present study the MnOx nanostructures electrodeposited on the glassy carbon electrode modified with nafion film, using cyclic voltammetry as electrodeposition technique. The proposed procedure appears to be a highly efficient method for the development of a new class of MnOx nanostructures with Peroxidase‐like activity, which can be used in fabrication of electrochemical sensor. The electrochemical activity of modified glassy carbon electrode (GCE) with MnOx /nafion film for detection of H2O2 is investigated by CV and differential puls voltammetry techniques. This modified electrode shows excellent electrocatalytic activity toward H2O2 reduction at unusual reduced overvoltage. The reduction potential of H2O2 is carried out at 0.576 V versus Ag/AgCl reference electrode in acetat buffer solution w
