In this work, we have used microemulsion method for synthesis of MnOx/C nanocomposite and investigated its electrochemical properties via fabrication of supercapacitor and non-enzymatic hydrogen peroxide (H2O2) sensor. In-situ inclusion of conducting carbon in manganese oxide (MnOx/C) enhances the network conductivity facilitating the charge transfer process which is beneficial for supercapacitor and sensing applications. MnOx/C provides high energy and power density, 31.6 Wh kg(-1) and 3.8 kW kg(-1) respectively and short relaxation time similar to 3 ms for fabricated cell (MnOx/C//MnOx/C) endowing excellent power delivery capacity. Furthermore, MnOx/C as sensor, exhibits excellent catalytic activity toward the oxidation of H2O2 and shows high sensitivity (0.37 mA mM(-1) cm(-2)) with low detection limit (0.5 M at an S/N of 3). Hence, this study provides new avenue for high performance supercapacitor and H2O2 detection. (C) 2017 Elsevier B.V. All rights reserved.