Highly porous carbon fibers based on rice straw and paper mulberry have been successfully prepared via wet spinning and carbonization process. From the comparison of the morphological structure and specific surface area, the porous carbon fibers derived from rice straw shows a high specific surface area of 2260 m2/g. This material exhibits excellent hydrogen storage properties with a gravimetric hydrogen uptakes of 4.35 wt% at 77 K and 10 bar.