In　a　typical　high-performance　perovskite　solar　cell　(PSC),　the　electron-transporting　layer　(ETL)　plays　a　critical　role　in　facilitating　the　transportation　of　the　photogenerated　carriers　from　perovskite　to　electrode.　In　the　present　work,　the　solution-processed　Nb2O5　film　is　successfully　prepared　to　serve　as　an　alternative　for　replacing　the　overwhelmingly　dominated　TiO2　ETL　with　a　facile　deposition　approach.　By　adjusting　the　spin-coating　process　of　the　precursor　solution,　the　best　power　conversion　efficiency　of　19.2%　is　achieved　in　the　Nb2O5-based　planar　PSC　when　the　thickness　of　C-Nb2O5　ETL　is　about　100　nm.　The　characterization　including　ultraviolet　photoelectron　spectroscopy,　electronic　impedance　spectroscopy,　and　photoluminescence　spectrum　results　elucidate　that　the　impressive　photovoltaic　performances　can　be　attributed　to　the　proper　Nb2O5　ETL　conductive　band,　the　lower　charge　recombination　rate,　the　more　efficient　extraction,　and　transportation　of　the　photogenerated　carriers　from　the　perovskite　absorber.