The invention discloses a preparation method of loofah sponge anti-adhesion dressing for the wound surface. According to the preparation method, loofah plant fibers are adopted as the base material, polysaccharide molecules are grafted through conjugation reaction, so that the tissue anti-adhesion property of the natural plant fiber dressing for the wound surface is improved, and the effective protection for the wound of the skin is realized. The loofah sponge anti-adhesion dressing for the wound surface can be directly applied to the wound surface, has the extremely excellent absorption effect, and is particularly suitable for treating the skin diseases including burns, pus, wound drainage, anabrosis and the like. The hydrophilic performance and tissue-adhesion-resisting property of the natural plant fiber dressing for the wound surface are obviously improved, and meanwhile, the toxic chemical crosslinking agent is not used, so that the biocompatibility and the safety of the dressing are improved. The process is simple, the cost is low, the modifying temperature is low, the grafting speed is high, and the method is suitable for large-scale industrial production.