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In this paper, the xLiFePO4.yLi3V2(PO4)3/C composite cathode materials were prepared via sol-gel method in order to combine the outstanding performance of LiFePO4 and Li3V2(PO4)3, in which analytic grade of LiH2PO4, FeC2O4·2H2O, NH4VO3 and C6H8O7·H2O were used as the main raw materials.Influence of the proportion, calcined temperatures, holding time on the phase composition, microstmcture and the electrochemical performance of the composites were studied.Results showed that the optimized synthetic conditions was that the molar ratio of LiFePO4 and Li3V2(PO4)3 equaled to 7∶1, the calcined temperature was at 700℃ and hold time was 8 h.The as-prepared composite cathode materials exhibited free particle sizes ranged between 40nm and 80nm, and with homogenous sizes distribution, also the particles were uniformly coated by an amorphous carbon layer.At 0.1C rate,the first discharge capacity of 7LiFePO4·Li3V2(PO4)3/C composites was up to 129.7mAh/g with the charge and discharge efficiency of 96.0%.At lC, 2C and 5C rate, the first discharge capacities of 7LiFePO4·Li3V2(PO4)3/C composites are 104.6, 89.3, and 71.6 mAh/g, respectively.After 30 cycles, the capacity retentions are 99.9, 95.1,98.6%, respectively, showing a good electrochemical stability.