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Abstract: Among promising substitutions for commercial graphite anodes for lithium ion batteries, SnO2 has a fourfold theoretical capacity of graphite (if the O element is completely reversible), while the oxygen reutilization is seriously hampered by poor conductivity of both the electron and Li+ ions. This work proposes a novel ternary architecture of SnO2@C quantum dots (QDs, with average diameter of 3.37 nm) grafted on graphene oxides, denoted as SnO2@C/G, via a facile and scalable one‐pot hydrothermal method. The SnO2@C/G show extraordinary long‐term cycling performance (1080 mAh g−1 at 200 mA g‐1 after 300 cycles) and rate capability (∼840 mAh g−1 at 2 A g−1). If excluding the contribution of carbon, the specific capacity of SnO2 is 1447 mAh g−1 at 200 mA g‐1, 96.9% of its theoretical capacity. The extraordinary performance is ascribed to ultrahigh reversibility of SnO2 QDs, good structural stability, and much better ionic/electronic diffusions confirmed by XPS, TEM, EIS, respectively. [ABSTRACT FROM AUTHOR]