Sol-gel processed niobium oxide (Nb2O5) thin-film was synthesized for a scaffold layer (SL) of methylammonium lead iodide-based perovskite film. Complementary characterizations, including scanning electron microscopy, X-ray diffraction, optical absorption spectroscopy have revealed that the Nb2O5 SL facilitates efficient crystallization of the perovskite film compared to the conventional mesoporous titanium oxide (m-TiO2) SL. Also, photoluminescence spectroscopy revealed the higher electron-extraction capability at the perovskite/Nb2O5 interface than the perovskite/m-TiO2 interface. The present sol-gel processed Nb2O5 SL and the superior optoelectronic properties of the overlying perovskite film suggest a promising avenue for high-performance and cost-effective perovskite solar cells.