Magnesium-based batteries have received much attention as promising candidates to next-generation batteries because of high volumetric capacity, low price, and dendrite-free property of Mg metal. Herein, we reported H2V3O8 nanowire cathode with excellent electrochemical property in magnesium-based batteries. First, it shows a satisfactory magnesium storage ability with 304.2 mA h g-1 capacity at 50 mA g-1. Second, it possesses a high-voltage platform of ∼2.0 V vs Mg/Mg2+. Furthermore, when evaluated as a cathode material for magnesium-based hybrid Mg2+/Li+ battery, it exhibits a high specific capacity of 305.4 mA h g-1 at 25 mA g-1 and can be performed in a wide working temperature range (-20 to 55 °C). Notably, the insertion-type ion storage mechanism of H2V3O8 nanowires in hybrid Mg2+/Li+ batteries are investigated by ex situ X-ray diffraction and Fourier transform infrared. This research demonstrates that the H2V3O8 nanowire cathode is a potential candidate for high-performance magnesium-based batteries.