As an advanced anode material for lithium-ion batteries, tin-chalcogenides receive substantial attention due to their high lithium-ion storage capacity. Here, tin chalcogenide (SnSe0.5S0.5) nanoplates are synthesized using a facile and quick polyol-method, followed by heating at different temperatures. Results show that the as-prepared of SnSe0.5S0.5 heated at temperature of 180 °C exhibits the best electrochemical performance with an outstanding discharge specific capacity of 1144 mA h g−1 at 0.1 A g−1 after 100 cycles and 682 mA h g−1 at 0.5 A g−1 after 200 cycles with a high coulombic efficiency (CE) of 98.7%. Even at a high current density of 5 A g−1, this anode material delivers a specific capacity of 473 mA h g−1. The high electrochemical performance of SnSe0.5S0.5 is shown by in-situ XRD analysis to originate from an enhanced Li+ intercalation and an alloy conversion process.