LiFePO4/C nano-particles were synthesized by microwave assisted carbothermal reduction method, using LiOH•H2O,FePO4•2H2O and sucrose as raw materials. LiFePO4/C samples with different particle sizes were prepared by heating at different temperatures in an industrial microwave oven. The samples were characterized by X-ray diffraction, field emission scanning electron microscopy, laser particle sizer analysis and electrochemical performance test. The results showed that the average size of samples is about 100 to 300 nm. The first discharge capacity decreased with the increase of temperature. The LiFePO4/C particles prepared at temperature of 700°С for 15 min exhibited the best capacity of 156.9mAh/g at 0.2C rate, and had just ~6% capacity loss after 50th cycles.