Stannate, CoSnO3, which mixes the elements Co and Sn evenly at the atomic level, was used as precursor to prepare CoSnC by a modified carbothermal reduction method. The synthesis process was characterized by differential thermal analysis (DTA) and X-ray diffraction (XRD). The particle feature was evaluated by transmission electron microscopy (TEM). The results indicated the as-prepared composite has a well-coated carbon layer that effectively prevents the encapsulated, low melting point alloy from out-flowing in a high-temperature treatment process. In addition, this structure, CoSn x grains surrounded by carbon, prevents aggregation and pulverization of nanosized, tin-based alloy particles during charge/discharge cycling and improves the cycling stability of the alloy. The synthesized CoSnC integrates the merits of intermetallic compounds and nanosized anode materials and delivers a reversible capacity of 450mAhg−1 with a capacity retention of 72% after 50 cycles.