Three dimensional (3D) nano-LiMn0.6Fe0.4PO4@C/CNT composite was successfully synthesized by an oleylamine-assisted solvothermal method. The prepared composite showed excellent electrochemical performance, especially superior high rate capability. It could deliver a specific discharge capacity of 103.1 mAh/g, even at 80 C. The superior high rate performance of the as-prepared LiMn0.6Fe0.4PO4@C/CNT electrode is attributed to its unique 3D conducting network: (1) the prepared LiMn0.6Fe0.4PO4@C active particles were in nano-scale with a size of 30–50 nm; (2) LiMn0.6Fe0.4PO4 nanoparticles were uniformly coated by amorphous carbon with a thickness of 3 nm; (3) the graphitized conductive CNTs were dispersed homogenously among the LiMn0.6Fe0.4PO4@C active particles. The synergistic effect of the nanoscale amorphous carbon coated LiMn0.6Fe0.4PO4@C active particles and the graphitized CNTs reduces the diffusion path of the lithium ions and benefits the transference ability of electron.