Carbon coated Na5V12O32 ultralong nanowires were synthesized by hydrothermal and solid-state reaction methods As a cathode material for sodium-ion batteries (SIBs), carbon coated Na5V12O32 ultralong nanowires exhibit high electrochemical performance with the redox potential ca. 2.8 V vs. Na+/Na, delivering initial discharge capacity of 105 mAh g(-1) at a rate of C/50. Furthermore, Carbon coated Na5V12O32 ultralong nano wires have the tap density of 3.2 g cm(-3) and volumetric energy density 940 Wh L-1. Results are confirmed that the carbon coating film with 10 nm thickness could effectively improve the electrochemical performance, and carbon coated Na5V12O32 ultralong may be used as cathode material for SIBs with highly environmental friendship and low cost.