Li–Mn–Sb–O composites (n_Li : n_Mn : n_Sb = 1.1 : 2 : 0.1) were synthesized via a ball milling technique and a solid state reaction method. The morphology, structure and electrochemical behavior were characterized by means of SEM, X-ray diffraction analysis and electrochemical charge–discharge tests. XRD analysis confirms that the as-prepared product is a complex composite of antimony-doped lithium manganese oxide and manganese-doped lithium antimony oxide. The composite calcinated at 750 °C consists of spherical-like nanoparticles with particle size ranging from 20–100 nm. A reversible capacity of about 94 mA h g⁻¹ remains after 40 cycles for the composite, when it is cycled at a voltage of 2.85–4.8 V. The rate performance and EIS results indicate that the capacity retention of the composite is superior to that of pure LiMn₂O₄.