LiFePO4/N-doped C composites with core–shell structures were synthesized by a convenient solvothermal method. Cetyltrimethylammonium bromide (CTAB) and glucose were used as nitrogen and carbon sources, respectively. The growth of LiFePO4 nanocrystals was regulated by CTAB, resulting in an average particle size of 143 nm for the LiFePO4/N-doped C. The N atoms existed in the carbon of LiFePO4/N-doped C in the form of pyridinic N and graphitic N. The LiFePO4/N-doped C composites delivered discharge specific capacities of 160.7 mAh·g−1 (0.1 C), 128.4 mAh·g−1 (5 C), and 115.8 mAh·g−1 (10 C). Meanwhile, no capacity attenuation was found after 100 electrochemical cycles at 1 C. N-doping enhanced the capacity performance of the LiFePO4/C cathode, while the core–shell structure enhanced the cycle performance of the cathode. The electrochemical test data showed a synergistic effect between N-doping and core–shell structure on the enhancement of the electrochemical performance of the LiFePO4/C cathode.