A modified sol–gel process with the aid of a structure-directing surfactant was employed to synthesize crystalline mesoporous Nb2O5 nanoparticles under mild conditions. The XRD result revealed that the synthesized Nb2O5 nanoparticles exhibit a single crystalline orthorhombic phase without any impurities. The N2 adsorption–desorption isotherm, pore size distribution, SEM, and high resolution TEM results clearly indicated that the synthesized Nb2O5 nanoparticles possess monomodal pore size distribution in the mesoporous range with uniform porous structure. The synthesized mesoporous Nb2O5 has a specific surface area of 97.5m2/g, a mean mesopore diameter of 12.2nm, and a total pore volume of 0.41cm3/g. Additionally, the UV–visible spectrum result suggested that the synthesized mesoporous Nb2O5 is a potential UV light-absorbing material.