The mesoporous NH4V4O10 nanoflowers have been synthesized as cathode materials for lithium-ion batteries by a beta-cyclodextrin (beta-CD)-assisted hydrothermal method. The flowers with clear outline and uniform size are composed of nanoflake for 200-300 nm in width and the length up to micron levels. There are mesopores with an average size of 3 nm on the surface of petals. The mesoporous nanoflowers deliver a high capacity of 242.8 mAh g(-1) at a current density of 200 mA g(-1) between 2.0 and 4.0 V. Even at high current density of 1000 mA g(-1), it still retains 103.5 mAh g(-1) (about 64.9% capacity) after 200 cycles. Besides, compared with the samples prepared without beta-CD, the electrode of the mesoporous nanoflowers has a high rate of lithium transition during the lithiation/delithiation process. These results demonstrate such mesoporous NH4V4O10 nanoflowers could be promising as a high-performance cathode for lithium-ion batteries.