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Nano-particle FePO4 and Fe1.xCexPO4 (x=0.02,0.04,0.08) cathode materials were synthesized by microemulsion method.The samples were prepared via a microemulsion system in a H2O/cyclohexane/Triton x-100/n-butyl alcohol at different temperatures (30 ℃, 45 ℃, 50 ℃, 60℃) and then sintered at 380 ℃and 460 ℃ for 3 h.The thermal stability, structure and morphology were investigated by means of TG/DCS, X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), and the electrochemical properties were characterized by cyclic voltammetry (CV) and galvanostatic charge and discharge tests.Results show that synthesis temperature has a great influence on the performances of FePO4, and the sample synthesized at 45℃ shows the best performance with a diameter of about 20 nm and a high discharge initial specific capacity of 142 mAh/g and retaining 123 mAh/g after 20 cycles at 0.1 C.The Ce-doped FePO4, Fe1-xCexPO4 (x=0.02,0.04,0.08), can effectively improve the electrochemical properties of FePO4 cathode materials.The Fe0.96Ce0.04PO4 exhibits a initial discharge capacity of 158.2 mAh/g and retains 152 mAh/g after 25 cycles at 0.1 C.Hence, Fe0.96Ce0.04PO4 is a promising candidate for cathode materials of lithium ion batteries.