LiFePO4/C and LiFe0.97Sn0.03PO4/C composites were synthesized by a novel preparation method of high-temperature high-energy ball milling (HTHEBM). The composites were characterized by XRD, SEM, and electrochemical performance tests. The results indicate that the physical properties and electrochemical performance of the LiFe0.97Sn0.03PO4/C sample were greatly improved by the introduction of SnO2. The improved discharge capacities of the sample are 159 mA h g(-1) at 0.1 C and 144 mA h g(-1) at 5 C, and the capacity retention is 99% after 30 cycles, tested at 5 C.