Multi-yolk-shell SnCo@N-doped carbon nanocages with controllable carbon shell thickness are well fabricated by a novel approach. The multi-yolk-shell SnCo@N-doped carbon nanocages form an enough void volume to compensate the volume expansion of SnCo nanoparticles during Li+ insertion. To optimize the electrochemical properties, SnCo@N-doped carbon nanocages with controllable carbon shell thickness can be tailored by coating polydopamine (PDA) with various thicknesses on CoSn(OH)6 hollow nanocubes in the second step of the synthesis process. Multi-yolk-shell SnCo@N-doped carbon nanocages with the optimized shell thickness exhibit a high initial discharge capacity (1025 mAhg−1) and remarkable cyclic stability (611 mAhg−1 after 100 cycles) as Li-ion batteries anode. This work may open a wonderful way for the rational design of alloy@carbon composites with tailorable structures for next-generation anode nanomaterials in Li-ion battery.