Wound bed preparation in skin wound area can be carried out with a hydrogel sheet prepared by spreading a hydrogel containing a water-soluble polymer, glycerin and water on a laminated two-layer film composed of a polyurethane film and a hydrophobic fiber, and having the moisture permeability of 200~2000 (g/m2/24h).本發明係關於藉由使用塗抹含有水溶性高分子、甘油、水之水凝膠於由聚胺基甲酸酯薄膜及疏水性纖維所成之2層層合薄膜,且其透濕度為200~2000(g/m2/24h)之水凝膠薄片,可進行皮膚創傷患處之傷口床環境調整。