Considering the much huger exploitable reserves of potassium compared with lithium, researchers regard potassium ion batteries (PIBs) as a promising candidate to LIBs. [4] The anode being an integral part of PIBs, its specific capacity plays a critical role in determining the energy density of the battery. Up to now, researchers have developed various anode materials for PIBs such as intercalation type, alloying type, organic type, and conversion type. [5] Amongst them, tin-based anode materials, especially tin chalcogenides, have amassed widespread interest due to their considerable theoretical specific capacity. [6] However, tin chalcogenides suffer from universal shortcomings such as insufficient electronic conductivity, significant volume effect, and non-negligible shuttle effect of potassium chalcogenide (typical discharged product). [7] Consequently, it is crucially important to adopt appropriate modifications for excavating the application prospect of tin chalcogenides anode materials.As a member of tin chalcogenides, SnSe has a narrower band gap than SnS/SnS 2 , which indicates that SnSe is equipped with higher electronic conductivity, benefiting the utilization of its intrinsic high capacity. [8] In addition, compared with polysulfides, the shuttle effect of polyselenides is less critical, and the capacity decay is slighter consequently. [9] Predictably, SnSe will exhibit superior performance in capacity retention. Despite the enormous advantages of the SnSe material have been proved in LIBs and SIBs, however, there are few reports on SnSe-based anode in PIBs until 2021, when Verma et al. reported the first application of SnSe-based anode Tin chalcogenides are regarded as promising anode materials for potassium ion batteries (PIBs) due to their considerable specific capacity. However, the severe volume effect, limited electronic conductivity, and the shuttle effect of the potassiation product restrict the application prospect. Herein, based on the metal evaporation reaction, a facile structural engineering strategy for yolk-shell SnSe encapsulated in carbon shell (SnSe@C) is proposed. The internal void can accommodate the volume change of the SnSe core and the carbon shell can enhance the electronic conductivity. Combining qualitative and quantitative electrochemical analyses, the distinguished electrochemical performance of SnSe@C anode is attributed to the contribution of enhanced capacitive behavior. Additionally, first-principles calculations elucidate that the heteroatomic doped carbon exhibits a preferable affinity toward potassium ions and the potassiation product K 2 Se, boosting the rate performance and capacity retention consequently. Furthermore, the phase evolution of SnSe@C electrode during the potassiation/depotassiation process is clarified by in situ X-ray diffraction characterization, and the crystal transition from the SnSe Pnma(62) to Cmcm(63) point group is discovered unpredictably. This work demonstrates a pragmatic avenue to tailor the SnSe@C anode via a facile structural eng...