In this work, carbon cloth (CC) was employed as a substrate onto which alpha-MnO2 nanowires were grown hydrothermally as a secondary support structure. In NaBH4 aqueous solution, the surface of the MnO2 was reduced at room temperature to form alpha-MnO2/Mn3O4 hierarchical structure. At a current density of 2 A g(-1), the specific capacitance of the alpha-MnO2/Mn3O4@CC was found to be 181 F g(-1). The energy density of the asymmetric supercapacitor (ASC) assembled by alpha-MnO2/Mn3O4@CC and activated carbon reaches 118.3 Wh kg(-1). After 4000 cycles at a current density of 1 A g(-1), the 88% of the capacitance was retained demonstrating good cycle stability. The designed multi-level structure can effectively prevent the stacking and agglomeration of the nanowires, and provides high energy density and good cycle stability in ASC. These results provide a good experimental foundation for the development of advanced, wearable, and energy storage devices.