A simple and reliable design of the non-enzymatic sensor capable of instant detection of broad range of hydrogen peroxide (H2O2) concentrations in various water-based matrixes has been presented. Manufacturing of the sensor was based on the manganese dioxide (MnO2)-non-functionalized single walled carbon nanotubes (SWCNTs) - Nafion nanocomposite modified glassy carbon electrode (MnO2/SWCNTs-Nf/GCE). The electro-chemical behavior of hydrogen peroxide at this sensitive platform was verified by the cyclic voltammetry and amperometry. The obtained results have demonstrated that the modified GCE exhibited an excellent electrocatalytic activity towards hydrogen peroxide. The parameters related to this sensor, such as amount of MnO2, applied potential and pH value were optimized to attain a broad working linear range 5.0 x 10(-6) to 3.0 x 10(-3) M, with detection limit of 0.52 x 10(-6) M (17.7 ppb) of detection H2O2. Developed electrode was tested for stability and accuracy measurements in environmental/biological conditions, such as pH and interference of common ions, namely calcium, magnesium, nickel, copper, bicarbonate and citrate, showing an excellent stability and repeatability in tested ranges. (C) 2016 Elsevier B.V. All rights reserved.