Here we propose, for the first time, a new and green ethanol-thermal reaction method to synthesize high-quality, pure thiophene-sulfur(S) doped reduced graphene oxide (rGO), which establishes an excellent platform for studying doping effects on the physical/chemical properties of this material.We have quantitatively demonstrated that the conductivity enhancement of thiophene-S doped rGO is not only caused by the more effective reduction induced by S doping, but also by the doped S atoms, themselves.Furthermore, we demonstrate that the S doping is more effective in enhancing conductivity of rGO than N doping due to its stronger electron donor ability.Finally, the dye-sensitized solar cell (DSCC) employing the S-doped rGO/TiO2 photoanode exhibits much better performance than undoped rGO/TiO2, N-doped rGO/TiO2 and TiO2 photoanodes.It therefore seems promising for thiophene-S doped rGO to be widely used in electronic and optoelectronic devices.