We here report on the preparation and Li-ion battery anode application of ultrasmall Sn nanoparticles (∼5 nm) uniformly embedded in spherical hollow carbon. The novel Sn-C composite shows a high Li-storage capacity (743 mA h g-1 at 0.5 A g-1) with unprecedentedly high cyclic stability (92.1% capacity retention after 6000 cycles at 4 A g-1).