Unique hollow Fe3O4/C spheres are prepared by a simple one-pot solvothermal method, with spinel structure and 750nm in diameter identified by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. The hollow Fe3O4/C spheres exhibit excellent cycling and rate performance as anode material for lithium ion batteries, delivering reversible specific capacities of 984mAhg−1 even after 70 cycles at 0.2C, 620mAhg−1 at 2C, and 460mAhg−1 at 5C, respectively. Lithium insertion mechanisms are also proposed in terms of the ex situ XRD analysis of the electrodes after discharged and charged to certain voltages together with cyclic voltammetry (CV) and voltage profile.