Natural dye sensitizers were extracted from Terminalia catappa (R), Azadirachta indica (G), and Clitoria ternatea (B) using water as a solvent to sensitize the bare photo-anodes of N-DSSCs. The average crystalline size of a bare TiO2-based photo-anode was compared with a composite photo-anode which includes 1 wt% of MoO3. The anchoring capability of extracted sensitizers (R, G, and B) toward metal oxides was confirmed with a favorable functional group. Through UV–Vis–DRS Spectra, the light-harvesting capability to collect light was compared for each composite and a TiO2-based photo-anode that had been sensitized with respective sensitizer R, G, and B. The photo-catalytic performance of dye-anchored pure TiO2 and composite-based photo-anodes have been analyzed through recombination rate. Photovoltaic parameters of assembled N-DSSCs were calculated from the J–V graph. The overall efficiency of N-DSSCs incorporated with 1wt% MoO3 -based photo-anode sensitized with Terminalia catappa (as RB), Azadirachta indica (as GB), and Clitoria ternatea (as BB) shows diminished results than that of respective pure TiO2-incorporated photo-anode-based N-DSSCs.