A method of manufacturing wound dressing, first adding the activated carbon fibers into a foam precursor where each of the activated carbon fibers has a diameter of 2-15 μm and a length of 40-1500 μm. The foam precursor is made of a polymeric material, and the activated carbon fibers is 0.1-5 wt % of the activated carbon fibers plus the polymeric material. Then foaming the foam precursor to make it become an absorbing member having a plurality of pores where the activated carbon fibers partially protrude into the pores. Thus, the tissue fluid leaking from the wound can be absorbed by the absorbing member to prevent the wound from soakage and the activated carbon fibers inside the absorbing member can emit far-infrared rays to promote the blood circulation around the wound for quickening healing of the wound.