The invention relates to an anti-scouring method for a marine structure. The method comprises the steps that a soft protection device is laid at a preset seabed potion around a pile foundation of the target marine structure; and the soft protection device is firmly connected to the corresponding pile foundation, so that a seabed base face around the pile foundation is prevented from scoured by waves or water flows. The method provided by the invention makes full use of a mechanical mechanism of scouring. The method is characterized in that the soft protection device is laid on the seabed base face around the pile foundation of the marine structure, so that the part around the structure has higher resistance to the scouring of the waves and water flows.