A skin wound dressing is disclosed. The skin wound dressing comprises Tremella polysaccharide and alginate and is used to cover on a skin wound to accelerate wound healing. The Tremella polysaccharide is isolated from a hot water extract of Tremella fuciformis. The skin wound dressing is a Tremella polysaccharide composite fiber, a Tremella polysaccharide sponge or a Tremella polysaccharide hydrogel.