Constructing stable structure and efficient ion and electron diffusion pathways are critically important for high-performance anode materials of lithium-ion batteries. Herein, a unique nanocomposite composed of FeO/Fe2O3 (FexOy) nanoparticles in-situ wrapped within porous carbon framework has been successfully fabricated by an extremely facile and relatively green method, namely just calcinating the commercial ferric citrate in Ar atmosphere. Therefore, our strategy for preparing composites with unique structures has advantages of relative green and extreme simple compared with the commonly hydrothermal or solvothermal and followed by carbonization ways due to no use of various solvents and reagents, and additional time-and power-consuming hydrothermal or solvothermal heating treatment. Benefiting from the synergistic effect of FexOy nanoparticles and uniquely porous carbon framework, the as-achieved composite possesses robust structural stability and improved electrochemical kinetics. As a result, it exhibits superior lithium storage performance, delivering capacities of 606.4 and 526.6 mAh g(-1) at 200 and 1000 mA g(-1) after 450 and even 1200 cycles, respectively. Moreover, the advantages of relatively green and extremely facile preparation process, and good lithium storage performance may make this composite a promising anode candidate for next generation of high-performance lithium-ion batteries.