MnO nanoparticles with diameter about 5nm are uniformly dispersed within a spherical carbon matrix by an in-situ adsorption approach. This unique nanostructure with rational design and engineering not only possesses large elastic buffering space to prevent MnO nanoparticles from agglomeration, but also improves lithium-storage properties because the carbon matrix provides continuous path for Li-ion and electron diffusion inside the composite spheres. The cell assembled with the nanostructure composite exhibits high reversible specific capacity of 501mAh/g (exceeding pure MnO particles of 199mAh/g) after 300 cycles at 0.5A/g, excellent cycling stability with 81% capacity retention after 300 cycles, and enhanced rate performance up to 161mAh/g at 5A/g with only 13% capacity fade after 200 cycles. Due to the scale-producible fabrication steps under low temperature for this approach, the method can be used for the preparation of other nanostructures with high performance.