To mitigate the issues of severe volume expansion (>259%) and electrode pulverization in Sn-based anodes (theoretical specific capacity: 993 mA·h/g) for next-generation lithium-ion batteries (LIBs), we designed a CoSn₂/Sn@C core−shell structure to accommodate the volume change and stabilize the cycling performance of LIBs. The Co₃O₄/SnO₂ nanocubes were firstly prepared from CoSn(OH)₆ precursor via a sintering and oxidation process in an air atmosphere. Subsequently, glucose was coated on Co₃O₄/SnO₂ nanocubes, and then the composites were sintered under a reduction atmosphere to form CoSn₂/Sn@C nanocubes with a core−shell structure. The CoSn₂/Sn@C nanocubes exhibited shortened ion transport paths and excellent reaction kinetics due to their well-designed structures and controlled compositions. The electrochemical test results show that an excellent specific capacity of 672.2 mA·h/g after 500 cycles at a current density of 1 A/g was maintained for CoSn₂/Sn@C electrode. The core−shell structure design of the elaborated CoSn₂/Sn@C nanocubes holds significant implications for the development of high-performance anode materials for LIBs.