Niobium and vanadium oxides nanocomposites are synthesized using a facile sol–gel process, and characterized by scanning and transmission electron microscopy. X-ray diffraction results show that the nanocomposites are composed of Nb2O5 and its solid solutions. Such nanocomposites exhibit both significantly improved rate and cycling stability. At a current density of 1Ag−1, the nanocomposites deliver more than three times of capacity than pure Nb2O5, and remain ~95% of its initial capacity after 50 cycles. Possible synergistic mechanism between the constituent components of the nanocomposites is also proposed.