Highly ordered N-doped mesoporous niobium oxide (NMNb) was prepared via a facile solid state reaction method using urea as a nitrogen source. The mesoporous structure of niobium oxide (MNb) is beneficial to the N dopant that is effectively incorporated into the lattice of MNb, resulting in a significantly enhanced visible light response. The hydrogen generation efficiency over the optimized N-doped MNb photocatalyst was 14.8 times as high as that from N-P25 under 5 h visible light irradiation. The improved photocatalytic activity of NMNb was mainly due to the fact that the inherited ordered mesostructure of NMNb could offer more active sites for the photocatalytic reaction, as well as accelerate the photogenerated electron-hole pair transfer and separation.