The core-shell structural Fe3O4@C nanospheres have been facilely fabricated using ferrocene as a starting material.(*) The obtained architecture shows unique morphology and, as an anode of half cell lithium-ion batteries, delivers an initial coulombic efficiency as high as 80% and a high reversible capacity of 736mAhg−1 at 0.3Ag−1 after 80 cycles. Even at an ultrahigh current density of 10Ag−1, the reversible capacity is 234mAhg−1. Also, Fe3O4@C nanospheres electrode was paired with commercial LiCoO2 electrode to design a novel full cell, which shows a superior electrochemical performance.