The MnO/graphene hybrid nanocomposites were prepared by an in situ reduction method. The MnO2 nanorods were attached on the graphene oxides (GOs) to form the MnO2/GO nanocomposites, which were reduced to the MnO/graphene hybrid under argon atmosphere. As the anode material for the lithium ion batteries, the MnO/graphene electrodes delivered a high initial charge capacity up to 747 mAh g(-1) and a stable capacity of 705.8 mAh g(-1) after 100 cycles, which is much superior to pure MnO with initial charge capacity of 456 mAh g(-1) and the stable capacity of 95.6 mAh g(-1) after 100 cycles. The scanning electron microscope images of the MnO/graphene hybrid nanocomposites after cycling demonstrated that the graphene could prevent the MnO from aggregating during the charge/discharge process.