In this study, we produced reduced graphene oxide (RGO) by reduction of graphene oxide (GO) in Teflon-lined autoclave, maintained at 100 degrees C for 12 hours, and coated on the anode gas diffusion layer (GDL) of a proton-exchange membrane fuel cell (PEMFC) to improve the cell performance. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analysis showed the presence of residual oxygen-containing functional groups in RGO. Field-emission scanning electron microscopy images revealed the uniform and adequate coating of the GDLs with RGO. The wettability of RGO-coated GDL was determined by the sessile drop method and has optimum contact angle 117 degrees. The power densities for the membrane electrode assembly (MEA) with RGO coated on the anode GDL were 30.92%, 41%, and 36.20% higher than those for the MEA without the RGO coating at anode gas humidified temperatures of 25 degrees C, 45 degrees C, and 65 degrees C, respectively.