SnO2 nanocrystals and reduced graphene oxide (rGO) nanoplatelets composite was prepared in a one-pot hydrothermal route utilizing the redox reaction between Sn2+ ions and GO. The dye-sensitized solar cells (DSSCs) were assembled with N3-dipped SnO2/rGO photoanode, Pt plate as the counter electrodes, and I –/I3– as the electrolyte. Flower-like SnO2 nanocrystals dispersed on plate-like rGO to constitute a composite photoanode film were characterized by scanning electron microscope, transmission electron microscope, and XRD measurements. Photoelectric properties of DSSCs were analyzed with volt–ampere (J–V) characteristic curve and electrochemical impedance spectroscopy. The results show that DSSC with SnO2/rGO nanocomposites as the photoanode exhibited better photoelectric properties than pure SnO2-DSSC due to a more stable nanocrystal oxide particle/rGO platelet structure. When the mass ratio of GO and SnCl2 2H2O was 20%, the short-circuit current density (J sc) of SnO2/rGO-DSSC was up to 15.52 mA/cm2, and the photoelectric conversion efficiency increased 34% compared to pure SnO2-DSSC. The synergistic effect of SnO2/rGO nanocomposites on electron transportation in the photoanode and photoelectricity conversion efficiency of DSSCs was discussed.