Spinel Li4Ti5O12 (LTO) is the safest commercial anode for power batteries owing to its stability, zero strain and Li dendrites free, but its inherent insulating characteristic seriously limits its high-rate capability. Nitrogen-doped LTO/C (NCLTO) is firstly synthesized by thermal decomposition of an amorphous titanate crosslinking g-C3N4 inorganic polymer and then reaction with lithium salts utilizing a simple solid state reaction. The doping nitrogen has a fair distribution which allows fast transportation of lithium ions, and the content of nitrogen is tunable through control the decomposition time of g-C3N4. It exhibits a better high-rate capability and cycling performance than that of LTO, which delivers a high capacity of 122mAhg−1 after 500 cycles at a current density of 10C with 102% capacity retention while the capacity retention of only 50.5% for pure LTO. Furthermore, the NCLTO also exhibits an overwhelming advantage of high-rate performance than LTO owing to the introduced conductive nitrogen-doped carbon and TiN.