Nanostructured MnO2/nitrogen doped graphene (MnO2/N-RGO) hybrids were synthesized by a facile and economic method at low temperature with ammonia pretreatment. Characterizations show nitrogen atoms were embedded into graphene lattice during pretreatment followed by MnO2 nanowires anchored onto graphene flakes. Compared with MnO2/graphene (MnO2/RGO) hybrids, the novel hybrids exhibited higher capacitance value and enhanced cyclic stability. At a current density of 2mAcm−2, the capacitance of as-obtained hybrids was up to 275.2Fg−1 and retained 98.3% of initial capacitances after 1000 cycles. These results illustrate that ammonia pretreatment is effective for nitrogen atom doping and the hybrids are potential as electrode materials for supercapacitors.